Enable BigQueryMetrics by default

[JayajP]

New BigQuery Metrics will be auto-enabled after this change. Metrics can be disabled for a pipeline by passing the experiment disable_per_worker_metrics.

---

Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily:

• Mention the appropriate issue in your description (for example: addresses #123), if applicable. This will automatically add a link to the pull request in the issue. If you would like the issue to automatically close on merging the pull request, comment fixes #<ISSUE NUMBER> instead.
• Update CHANGES.md with noteworthy changes.
• If this contribution is large, please file an Apache Individual Contributor License Agreement.

See the Contributor Guide for more tips on how to make review process smoother.

To check the build health, please visit https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI or the workflows README to see a list of phrases to trigger workflows.

[JayajP]

Run Java Precommit

[github-actions]

Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

[Abacn]

Thanks, the change LGTM. Would you mind note this change in CHANGES.md ?

personally since the logics were just merged today. I would prefer flipping the flag in the next release cycle (2.57.0), taking more time to test.

[Abacn]

@JayajP merged, would you mind open a new PR to announce (promote) this change in CHANGES.md ?