$ git clone -n https://src.fedoraproject.org/rpms/gsl.git /var/lib/mock/f45-build-13079-446/root/chroot_tmpdir/scmroot/gsl
Cloning into '/var/lib/mock/f45-build-13079-446/root/chroot_tmpdir/scmroot/gsl'...
$ git fetch origin 20fb004c5eafb1e4b0c261fe1e650ccd249fc40f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gsl
 * [new ref]         20fb004c5eafb1e4b0c261fe1e650ccd249fc40f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 20fb004 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild