chore(parallel tests): revamp parallel test outputs for searchability and clarity

[chalmerlowe]

Warning

• Revert Before Merge: The changes to setup.py files and the dummy test in google-cloud-dns are only for verification and will be reverted before this PR is merged, hence the do-not-merge label.

Problem

The current parallel system test output can be difficult to read and search, especially when dealing with many packages or mixed results (where some test sessions pass and others fail). Logs for successful packages were often hidden, and searching for specific package results required scanning through large blocks of text.

Solution

This PR revamps the output format of parallel system tests to improve readability and searchability (CTRL+F).

Specific Changes

• Standardized Segments: Clearly segregates Succeeded and Failed packages.
• Search Tokens: Introduces unique, consistent tags (@SUMMARY, @FAILED, @SUCCEEDED, @PACKAGE) for quick navigation (i.e. via CTRL+F) to key sections of the logs.
• Robust Logging: Ensures logs for both succeeded and failed packages are displayed correctly.
• Noise Reduction: Removes redundant wrapper chatter (like Configuring environment...).
• Mixed Results Handling: Packages with mixed results (some sessions succeed, some fail) are grouped under the @FAILED section to ensure visibility, with clear labels indicating which session(s) need attention.

Note

• Temporary Test Setup: This PR includes temporary changes to 4 fast packages (google-cloud-dns, google-cloud-translate, google-cloud-speech, google-cloud-access-approval) to demonstrate the new layout and verify handling of mixed results.
• Focus on system.sh: The core of this PR is the changes to .kokoro/system.sh.
• Lint failures: are due to the minor triggers added and will disappear when the triggers are reverted.

🔍 Search Cheat Sheet for Reviewers

Goal	Search Term (CTRL+F)
Jump to the Summary Table	@SUMMARY
Jump to Section for Failed Packages	@FAILED
Jump to Section for Succeeded Packages	@SUCCEEDED
Jump to a specific package	<package-name>
Jump directly to a Failed package	@PACKAGE (FAILED): <package-name>

[gemini-code-assist]

Code Review

This pull request revamps the parallelization output in the Kokoro system test script, renaming 'passed' packages to 'succeeded' and adding detailed log outputs for succeeded packages. It also introduces temporary configurations and a dummy test in google-cloud-dns to verify mixed test results. Feedback on these changes suggests removing the temporary experimental configurations and dummy test before merging. Additionally, it is recommended to avoid printing detailed logs for succeeded packages to prevent excessively large and noisy CI/CD build logs, opting instead to list only their names.

[chalmerlowe]

Do-not-merge added as a pre-emptive barrier to ensure that all fake tests and similar triggers are removed before merge.

[daniel-sanche]

LGTM, after trigger comments are removed

[chalmerlowe]

Removing trigger comments. Reckon I am gonna leave this unmerged until Monday since this has a broad ranging the can impact troubleshooting, debugging. Would like to be there when this first starts being used broadly to handle any unforeseen issues.