Fix http2 authority header in multiple endpoints scenario and bump up grpc from `v1.51.0` to `v1.52.0`#16324

serathius merged 2 commits intoetcd-io:mainetcd-io/etcd:mainfrom

chaochn47:bump-up-gRPCchaochn47/etcd:bump-up-gRPCCopy head branch name to clipboard