Clone jwage/changelog-generator, then run:
$ ./bin/changelog-generator generate --user=doctrine --repository=mongodb-odm --milestone=1.2.10
Clean up the changelog if necessary by checking milestone issues and differences from the last tag
Tag the release, using the changelog generated before as tag message:
$ git checkout 1.2.x && git tag -s 1.2.10
Push the tag to your own fork, waiting for travis-ci to complete successfully
If the above steps were successful, push the tag to the Doctrine repository, then create a new release using the GitHub UI for the tag you just pushed. Use the generated changelog in the release message.