Changelog for 0.77.0-rc.0 (#47958)

Summary:
Changelog as generated by rnx-kit + manual fixes.

Changelog: [Internal]

Pull Request resolved: #47958

Reviewed By: rshest, blakef

Differential Revision: D66498590

Pulled By: robhogan

fbshipit-source-id: 81efda2615f8e61be5f5922511362946f3ba3c6b

Author: robhogan