Update to 3.10.0-rc0 (#6660)
Update to 3.10.0-rc0 (#6660)

* Cherry pick changes on update_version.py #6643

* Update version to 3.10.0-rc-0

* Do not add rc0 to php packages.xml

protocolbuffers/protobuf-javascript,protocolbuffers/protobuf-javascript,protocolbuffers/protobuf-javascript,protocolbuffers/protobuf-javascript