$ git clone -n https://src.fedoraproject.org/rpms/perl-Test-Portability-Files.git /var/lib/mock/f45-build-26765-619/root/chroot_tmpdir/scmroot/perl-Test-Portability-Files
Cloning into '/var/lib/mock/f45-build-26765-619/root/chroot_tmpdir/scmroot/perl-Test-Portability-Files'...
$ git fetch origin 112a6d1452b9975c404ca70119a3526dbffc0bae:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Test-Portability-Files
 * [new ref]         112a6d1452b9975c404ca70119a3526dbffc0bae -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 112a6d1 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild