Removes module variable required in GraalVM 22.2

[pivotal-david-osullivan]

Summary

The env var USE_NATIVE_IMAGE_JAVA_PLATFORM_MODULE_SYSTEM is no longer needed & is showing a build warning, this PR removes setting it at build time.

Use Cases

Closes #273

Checklist

• I have viewed, signed, and submitted the Contributor License Agreement.
• I have linked issue(s) that this PR should close using keywords or the Github UI (See docs)
• I have added an integration test, if necessary.
• I have reviewed the styleguide for guidance on my code quality.
• I'm happy with the commit history on this PR (I have rebased/squashed as needed).

[anthonydahanne]

Hello, I just tried building the Java Native Sample app at https://github.com/paketo-buildpacks/samples/tree/main/java/native-image/java-native-image-sample

with:

 pack build mymavenapp --env BP_MAVEN_ACTIVE_PROFILES=native --clear-cache --builder paketobuildpacks/builder-jammy-buildpackless-tiny:latest  \
  -b paketo-buildpacks/ca-certificates \
  -b paketo-buildpacks/bellsoft-liberica \
  -b paketo-buildpacks/syft \
  -b paketo-buildpacks/maven \
  -b paketo-buildpacks/executable-jar -b paketo-buildpacks/spring-boot -b paketo-buildpacks/native-image

and I got in the logs:

[builder] Warning: The USE_NATIVE_IMAGE_JAVA_PLATFORM_MODULE_SYSTEM environment variable is deprecated and might be removed in a future release. Please refer to the GraalVM release notes.

like @scottfrederick mentioned: #273 (comment)

Then, I locally checked out this branch and built it locally and then try and build my native app:

pack build mymavenapp --env BP_MAVEN_ACTIVE_PROFILES=native --clear-cache --builder paketobuildpacks/builder-jammy-buildpackless-tiny:latest  \
  -b paketo-buildpacks/ca-certificates \
  -b paketo-buildpacks/bellsoft-liberica \
  -b paketo-buildpacks/syft \
  -b paketo-buildpacks/maven \
  -b paketo-buildpacks/executable-jar -b paketo-buildpacks/spring-boot -b workspaces/paketo-buildpacks/native-image       

and... I no longer had the warning from native-image !

All good!