Gradle Toolchain remove PropertyOrigin.java and other cleanups

[vmadalin]

After https://github.com/gradle/gradle/pull/28731/ PR was merged a small clean up is required to remove unused variables, PropertyOrigin and also other warnings.

Contributor Checklist

• [x] Review Contribution Guidelines.
• [x] Make sure that all commits are signed off to indicate that you agree to the terms of Developer Certificate of Origin.
• [x] Make sure all contributed code can be distributed under the terms of the Apache License 2.0, e.g. the code was written by yourself or the original code is licensed under a license compatible to Apache License 2.0.
• [x] Check "Allow edit from maintainers" option in pull request so that additional changes can be pushed by Gradle team.
• [x] Provide integration tests (under <subproject>/src/integTest) to verify changes from a user perspective.
• [x] Provide unit tests (under <subproject>/src/test) to verify logic.
• [x] Update User Guide, DSL Reference, and Javadoc for public-facing changes.
• [x] Ensure that tests pass sanity check: ./gradlew sanityCheck.
• [x] Ensure that tests pass locally: ./gradlew <changed-subproject>:quickTest.

[big-guy]

Thanks, I'll take a look for 8.9

[gitstream-cm[bot]]

Change Summary

This PR is 25.41% new code.

Platform	Added Lines	% of Total Line Changes	Deleted Lines	% of Total Line Changes	Files Changed	% of Total Files Changed
bt_ge_build_cache	0	0%	0	0%	0	0%
build_infrastructure	0	0%	0	0%	0	0%
core_configuration	0	0%	0	0%	0	0%
core_execution	31	25.41%	88	72.13%	12	85.71%
core_runtime	31	25.41%	88	72.13%	12	85.71%
documentation	0	0%	0	0%	0	0%
extensibility	0	0%	0	0%	0	0%
gradle_enterprise	0	0%	0	0%	0	0%
ide	0	0%	0	0%	0	0%
jvm	0	0%	0	0%	0	0%
kotlin_dsl	0	0%	0	0%	0	0%
release_coordination	0	0%	0	0%	0	0%
software	0	0%	0	0%	0	0%

[big-guy]

@bot-gradle merge