chore: update release notes (googleapis#3414)

chore: update release notes (googleapis#3385)

chore: release notes for v0.18.x (googleapis#3368)

Also update the ABI dumps.

chore: update readmes for release (googleapis#3306)

* chore: update readmes for release

* PR comments

chore: update release notes for v0.16 (googleapis#3284)

Includes the fix for corrupted resumable uploads.

chore: update README files (googleapis#3251)

* chore: update README files

update release notes [skip ci] (googleapis#3177)

* update release notes [skip ci]

* Address review comments.

Update release notes [skip ci] (googleapis#3038)

Create v0.12.x release branch

Create v0.12.x release branch