Improved examples [skip ci]

Author: ankane

examples/citus/pom.xml

@@ -5,6 +5,8 @@
     <artifactId>example</artifactId>
     <version>1</version>
     <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>

examples/cohere/pom.xml

@@ -5,6 +5,8 @@
     <artifactId>example</artifactId>
     <version>1</version>
     <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>

examples/loading/pom.xml

@@ -5,6 +5,8 @@
     <artifactId>example</artifactId>
     <version>1</version>
     <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>

examples/openai/pom.xml

@@ -5,6 +5,8 @@
     <artifactId>example</artifactId>
     <version>1</version>
     <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     </properties>
     <dependencies>