feat(init-templates): update init templates to use the current LTS version of Java (#27422)

This change allows users to use more up-to-date java functionality. Java 8 is now only supported in limited circumstances so we should not set that version here.

> REPLACE THIS TEXT BLOCK
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> Describe the reason for this change, what the solution is, and any
> important design decisions you made. 
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> Remember to follow the [CONTRIBUTING GUIDE] and [DESIGN GUIDELINES] for any
> code you submit.
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> [CONTRIBUTING GUIDE]: https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md
> [DESIGN GUIDELINES]: https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md

Closes #<issue number here>.

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: TheRealAmazonKendra

packages/aws-cdk/lib/init-templates/app/java/pom.xml

@@ -19,17 +19,16 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.8.1</version>
+                <version>3.11.0</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>17</release>
                 </configuration>
             </plugin>
 
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
                 <artifactId>exec-maven-plugin</artifactId>
-                <version>3.0.0</version>
+                <version>3.1.0</version>
                 <configuration>
                     <mainClass>com.myorg.%name.PascalCased%App</mainClass>
                 </configuration>

packages/aws-cdk/lib/init-templates/sample-app/java/pom.xml

@@ -16,16 +16,16 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.8.1</version>
+                <version>3.11.0</version>
                 <configuration>
-                    <source>1.8</source>
-                    <target>1.8</target>
+                    <release>17</release>
                 </configuration>
             </plugin>
+
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
                 <artifactId>exec-maven-plugin</artifactId>
-                <version>3.0.0</version>
+                <version>3.1.0</version>
                 <configuration>
                     <mainClass>com.myorg.%name.PascalCased%App</mainClass>
                 </configuration>