test: Update the gapic-generator and hermetic-build golden files' copyright to 2025

[zhumin8]

follow-up to #3513,

Changes in this PR:

• generated by mvn test -DupdateUnitGoldens from gapic-generator-java/. Note that unit tests without this change did not fail. Filed investigate if test golden files are orphaned #3556 to investigate and maybe remove these in the future.
• library-generation unit test golden files. They are causing test failures in https://github.com/googleapis/sdk-platform-java/actions/runs/12659566586/job/35278951040?pr=3462 These 2 files are used in unit tests to test logic in owlbot to insert header when they are missing. e.g.

  sdk-platform-java/hermetic_build/library_generation/owlbot/synthtool/languages/java.py

  Lines 113 to 116 in 67f5ea2

  	def fix_grpc_headers(grpc_root: Path, package_name: str = "unused") -> None:
  	"""Helper to ensure that generated grpc stub classes have appropriate license headers.
  	If the file does not already contain a license header, inject one at the top of the file.

[blakeli0]

Thanks Min! Can you please make it clear that these golden files do not fail the unit tests? And they might get cleaned up in the future.

[zhumin8]

Updated description to provide more info.

[zhumin8]

Hermetic library generation upon generation config change through pull requests / library_generation (pull_request) Failing after 31m

  File "/opt/hostedtoolcache/Python/3.12.8/x64/lib/python3.12/site-packages/release_note_generation/generate_pr_description.py", line 114, in get_repo_level_commit_messages
    raise ValueError(
ValueError: current_commit (f17e0aa, committed on 1734006769) should be newer than or equal to baseline_commit (3cef095, committed on 1736181309) (is this branch up to date with the base branch?).
Error: Process completed with exit code 1.

Based on description in script here:

sdk-platform-java/.github/scripts/hermetic_library_generation.sh

Lines 4 to 5 in 816b160

	# This script is used to, when a pull request changes the generation
	# configuration (generation_config.yaml by default) or Dockerfile:

I am not sure if this test should run on this pr?

UPDATE: hint from above error, merge main into this resolved it.

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud