$ git clone -n https://src.fedoraproject.org/rpms/perl-Plack-Test-ExternalServer.git /var/lib/mock/f45-build-25838-613/root/chroot_tmpdir/scmroot/perl-Plack-Test-ExternalServer
Cloning into '/var/lib/mock/f45-build-25838-613/root/chroot_tmpdir/scmroot/perl-Plack-Test-ExternalServer'...
$ git fetch origin b38568cfae0c296fda614abb640f5300868972b7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Plack-Test-ExternalServer
 * [new ref]         b38568cfae0c296fda614abb640f5300868972b7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b38568c Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild