$ git clone -n https://src.fedoraproject.org/rpms/qt5-qtwebengine.git /var/lib/mock/f38-build-711792-94150/root/chroot_tmpdir/scmroot/qt5-qtwebengine
Cloning into '/var/lib/mock/f38-build-711792-94150/root/chroot_tmpdir/scmroot/qt5-qtwebengine'...
$ git fetch origin 0103b75b86dec0cbe4b3143b9dba72e42ef7c32b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qt5-qtwebengine
 * [new ref]         0103b75b86dec0cbe4b3143b9dba72e42ef7c32b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 0103b75 Rebuild (qt5)