chore(main): release 2.21.0

[release-please[bot]]

:robot: I have created a release beep boop

2.21.0 (2024-07-31)

Features

• Enable hermetic library generation (#1462) (d142d9c)

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This PR was generated with Release Please. See documentation.

[cindy-peng]

/gcbrun

[release-please[bot]]

:robot: Created releases:

• v2.21.0 :sunflower:

[release-trigger[bot]]

Triggered job: cloud-devrel/client-libraries/java/java-datastore/release/stage (2024-08-05T21:24:50.954Z)

To trigger again, remove the autorelease: triggered label (in a few minutes).

[release-tool-publish-reporter[bot]]

The release build has started, the log can be viewed here. :sunflower:

[release-tool-publish-reporter[bot]]

:egg: You hatched a release! The release build finished successfully! :purple_heart: