Add a script to mirror php changes to protobuf-php (#5778)
Add a script to mirror php changes to protobuf-php (#5778)

* Add a script to mirror php changes to protobuf-php

* Create tag

google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf