Add new client for Buf/Protocol Buffers #5431

Job	Run time
test (ubuntu-latest, 27.2, false)	2m 8s
test (ubuntu-latest, 28.2, false)	2m 30s
test (ubuntu-latest, 29.4, false)	2m 29s
test (macos-latest, 28.2, false)	3m 37s
test (macos-latest, 29.4, false)	3m 39s
test (windows-latest, 27.2, false)	3m 2s
test (windows-latest, 28.2, false)	3m 36s
test (windows-latest, 29.4, false)	3m 41s
test (ubuntu-latest, snapshot, true)	1m 28s
test (macos-latest, snapshot, true)	2m 48s
test (windows-latest, snapshot, true)	5m 2s
	34m 0s

Provide feedback