Fixes#7982
Defines a package level proto library and its associated internal go_proto_library.
Deletes all existing api_go_proto_library, api_go_grpc_library, and go_package annotations in protos (they are not required and pollute the sources).
I deliberately avoided touching anything under udpa since it's being moved to another repository.
Risk Level: low
Testing: build completes
Signed-off-by: Kuat Yessenov <kuat@google.com>
Mirrored from https://github.com/envoyproxy/envoy @ d504fde0ffd97017d1ddff8caa9a3b46bba9ae48
data-plane-api(CircleCI)