Update protobuf to v21.5

[sagmor]

Just updated the hashes from #125.

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[sagmor]

CC @JohnTitor as I took over your change feel free to take it over if you want 👍
CC @loeffel-io as you requested this (I'm blocked on bufbuild/protoc-gen-validate#583 too 😅)

[comius]

Thanks @sagmor!!!

[JohnTitor]

Thanks! I totally forgot to update my PR.

[comius]

I also mirrored the files.