FIX: Upgrade RHEL 9 containers to Python 3.12 in CI (#396)

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[AB#41417](https://sqlclientdrivers.visualstudio.com/c6d89619-62de-46a0-8b46-70b92a84d85e/_workitems/edit/41417)

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### Summary   
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This pull request updates the PR validation pipeline to use Python 3.12
(available in RHEL 9.4+) instead of Python 3.9 for both x64 and ARM64
RHEL 9 containers. It also makes corresponding updates to the virtual
environment setup and build steps, and omits certain packages to avoid
conflicts.

**Python version upgrade and environment updates:**

* Updated all references and installation steps from `python3`/Python
3.9 to `python3.12`/Python 3.12 in the pipeline script, including
virtual environment creation and dependency installation.
[[1]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1104-R1114)
[[2]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1167-R1167)
[[3]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1184-R1183)
[[4]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1320-R1329)
[[5]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1386-R1385)
[[6]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1403-R1401)

**Package management improvements:**

* Omitted installation of `curl` and `wget` to avoid conflicts with
`curl-minimal` when setting up the Python 3.12 environment.
[[1]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1104-R1114)
[[2]](diffhunk://#diff-296c8f902bbd70f34ee1c8c32383c8c99165fe4c8e5b0f234f8f22246e56a621L1320-R1329)
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Author: bewithgaurav

eng/pipelines/pr-validation-pipeline.yml

@@ -982,6 +982,7 @@ jobs:
         ./build.sh
       "
     displayName: 'Build pybind bindings (.so) in $(distroName) ARM64 container'
+    retryCountOnTaskFailure: 2
 
   - script: |
       # Uninstall ODBC Driver before running tests
@@ -1101,18 +1102,17 @@ jobs:
         dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm
         subscription-manager repos --enable codeready-builder-for-rhel-9-$(arch)-rpms || dnf config-manager --set-enabled ubi-9-codeready-builder
         
-        # Install Python 3.9 (available in RHEL 9 UBI) and development tools
-        dnf install -y python3 python3-pip python3-devel cmake curl wget gnupg2 glibc-devel kernel-headers
-        dnf install -y python3-libs python3-debug
-        dnf install -y gcc gcc-c++ make binutils
-        dnf install -y cmake
+        # Install Python 3.12 (available in RHEL 9.4+) and development tools
+        # Note: curl and wget omitted to avoid conflicts with curl-minimal
+        dnf install -y python3.12 python3.12-pip python3.12-devel python3.12-libs gnupg2 glibc-devel kernel-headers
+        dnf install -y gcc gcc-c++ make binutils cmake
         # If that doesn't work, try installing from different repositories
         if ! which gcc; then
           echo 'Trying alternative gcc installation...'
           dnf --enablerepo=ubi-9-codeready-builder install -y gcc gcc-c++
         fi
         # Verify installation
-        python3 --version
+        python3.12 --version
         which gcc && which g++
         gcc --version
         g++ --version
@@ -1164,8 +1164,8 @@ jobs:
   - script: |
       # Install Python dependencies in the container using virtual environment
       docker exec test-container-rhel9 bash -c "
-        # Create a virtual environment with Python 3.9
-        python3 -m venv myvenv
+        # Create a virtual environment with Python 3.12
+        python3.12 -m venv myvenv
         source myvenv/bin/activate
 
         # Install dependencies in the virtual environment
@@ -1181,7 +1181,7 @@ jobs:
       # Build pybind bindings in the container
       docker exec test-container-rhel9 bash -c "
         source myvenv/bin/activate
-        ls /usr/include/python3.9
+        ls /usr/include/python3.12
         # Set compiler environment variables
         export CC=/usr/bin/gcc
         export CXX=/usr/bin/g++
@@ -1317,18 +1317,17 @@ jobs:
         dnf install -y https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm
         subscription-manager repos --enable codeready-builder-for-rhel-9-$(arch)-rpms || dnf config-manager --set-enabled ubi-9-codeready-builder
         
-        # Install Python 3.9 (available in RHEL 9 UBI) and development tools
-        dnf install -y python3 python3-pip python3-devel cmake curl wget gnupg2 glibc-devel kernel-headers
-        dnf install -y python3-libs python3-debug
-        dnf install -y gcc gcc-c++ make binutils
-        dnf install -y cmake
+        # Install Python 3.12 (available in RHEL 9.4+) and development tools
+        # Note: curl and wget omitted to avoid conflicts with curl-minimal
+        dnf install -y python3.12 python3.12-pip python3.12-devel python3.12-libs gnupg2 glibc-devel kernel-headers
+        dnf install -y gcc gcc-c++ make binutils cmake
         # If that doesn't work, try installing from different repositories
         if ! which gcc; then
           echo 'Trying alternative gcc installation...'
           dnf --enablerepo=ubi-9-codeready-builder install -y gcc gcc-c++
         fi
         # Verify installation and architecture
-        python3 --version
+        python3.12 --version
         which gcc && which g++
         gcc --version
         g++ --version
@@ -1383,8 +1382,8 @@ jobs:
   - script: |
       # Install Python dependencies in the container using virtual environment
       docker exec test-container-rhel9-arm64 bash -c "
-        # Create a virtual environment with Python 3.9
-        python3 -m venv myvenv
+        # Create a virtual environment with Python 3.12
+        python3.12 -m venv myvenv
         source myvenv/bin/activate
 
         # Install dependencies in the virtual environment
@@ -1400,7 +1399,7 @@ jobs:
       # Build pybind bindings in the ARM64 container
       docker exec test-container-rhel9-arm64 bash -c "
         source myvenv/bin/activate
-        ls /usr/include/python3.9
+        ls /usr/include/python3.12
         # Set compiler environment variables
         export CC=/usr/bin/gcc
         export CXX=/usr/bin/g++
@@ -1410,6 +1409,7 @@ jobs:
         ./build.sh
       "
     displayName: 'Build pybind bindings (.so) in RHEL 9 ARM64 container'
+    retryCountOnTaskFailure: 2
 
   - script: |
       # Uninstall ODBC Driver before running tests
@@ -1881,6 +1881,7 @@ jobs:
         ./build.sh
       "
     displayName: 'Build pybind bindings (.so) in Alpine ARM64 container'
+    retryCountOnTaskFailure: 2
 
   - script: |
       # Uninstall ODBC Driver before running tests to use bundled libraries