Bump google-protobuf from 3.6.1 to 3.7.0

Bumps [google-protobuf](https://github.com/protocolbuffers/protobuf) from 3.6.1 to 3.7.0.
- [Release notes](https://github.com/protocolbuffers/protobuf/releases)
- [Changelog](https://github.com/protocolbuffers/protobuf/blob/master/generate_changelog.py)
- [Commits](protocolbuffers/protobuf@v3.6.1...v3.7.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>