FIX: install requirements.txt in Windows build stage to fix psutil import error (#507)

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### Summary   
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This pull request makes a minor update to the Windows build pipeline by
adding the `psutil` package to the list of Python dependencies installed
during the build process.

* Build pipeline dependencies:
* Added `psutil` to the `pip install` command in
`OneBranchPipelines/stages/build-windows-single-stage.yml` to ensure it
is available during builds.

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Author: gargsaumya

OneBranchPipelines/stages/build-windows-single-stage.yml

@@ -131,7 +131,7 @@ stages:
               $ErrorActionPreference = "Stop"
               Write-Host "Installing Python dependencies..."
               python -m pip install --upgrade pip
-              python -m pip install setuptools wheel pybind11 pytest pyodbc
+              python -m pip install setuptools wheel pybind11 pytest psutil pyodbc
               Write-Host "Dependencies installed successfully"
             displayName: 'Install Python dependencies'