release: Merge `rc/v12.3.0` into `master`. #9335

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@gonfunko

The following contributors were found for this pull request:

✅ 5f21e9b Author: @gonfunko <go****ko@gmail.com>, <ad****n@google.com>
✅ 84933b9 Author: @maribethb <ma*****hb@google.com>
✅ ef235cf Author: @RoboErikG <ep****rn@google.com>, <RoboErikG@users.noreply.github.com>
✅ 90580a8 Co-Author: @dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
✅ d942189 Author: @michaela-mm <63740955+michaela-mm@users.noreply.github.com>
✅ be5f5a2 Author: @nianxy <nx****7@163.com>
✅ f10454c Author: @cpcallen <cpc******git@google.com>

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