$ git clone -n https://src.fedoraproject.org/rpms/perl-Event-RPC.git /var/lib/mock/f39-build-1572915-37795/root/chroot_tmpdir/scmroot/perl-Event-RPC
Cloning into '/var/lib/mock/f39-build-1572915-37795/root/chroot_tmpdir/scmroot/perl-Event-RPC'...
$ git fetch origin b15c3b651621e63526dbe70be37a13e3331eb9a9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Event-RPC
 * [new ref]         b15c3b651621e63526dbe70be37a13e3331eb9a9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b15c3b6 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild