$ git clone -n https://src.fedoraproject.org/rpms/gammaray.git /var/lib/mock/f40-build-2145798-50880/root/chroot_tmpdir/scmroot/gammaray
Cloning into '/var/lib/mock/f40-build-2145798-50880/root/chroot_tmpdir/scmroot/gammaray'...
$ git fetch origin f5effe8b2dd026ce43a96845a9717b8e5818da95:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gammaray
 * [new ref]         f5effe8b2dd026ce43a96845a9717b8e5818da95 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f5effe8 Drop BR: qtwebkit and add BR: qtwebengine instead