$ git clone -n https://src.fedoraproject.org/rpms/perl-IPC-System-Simple.git /var/lib/mock/f45-build-24215-602/root/chroot_tmpdir/scmroot/perl-IPC-System-Simple
Cloning into '/var/lib/mock/f45-build-24215-602/root/chroot_tmpdir/scmroot/perl-IPC-System-Simple'...
$ git fetch origin 1fd1c7fe63a5931d755e1b9cd69aef32e6926506:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-IPC-System-Simple
 * [new ref]         1fd1c7fe63a5931d755e1b9cd69aef32e6926506 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1fd1c7f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild