$ git clone -n https://src.fedoraproject.org/rpms/perl-Sentinel.git /var/lib/mock/f39-build-1656341-40543/root/chroot_tmpdir/scmroot/perl-Sentinel
Cloning into '/var/lib/mock/f39-build-1656341-40543/root/chroot_tmpdir/scmroot/perl-Sentinel'...
$ git fetch origin 6986aa72939eeae4f97ed0cb186de37d0642fe8f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Sentinel
 * [new ref]         6986aa72939eeae4f97ed0cb186de37d0642fe8f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6986aa7 Update to 0.07 and other changes