chore(main): release 2.1.5

[release-please[bot]]

:robot: I have created a release beep boop

2.1.5 (2023-09-21)

Bug Fixes

• deps: Update dependency quicktype-core to v23 (#486) (dbdd930)

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[release-please[bot]]

:robot: Release is at https://github.com/googleapis/google-cloudevents/releases/tag/v2.1.5 :sunflower: