$ git clone -n https://src.fedoraproject.org/rpms/ninja-build.git /var/lib/mock/f40-build-730389-103193/root/chroot_tmpdir/scmroot/ninja-build
Cloning into '/var/lib/mock/f40-build-730389-103193/root/chroot_tmpdir/scmroot/ninja-build'...
$ git fetch origin 712a3ef05392aa212c6b52db8817e1b626ccb1c0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ninja-build
 * [new ref]         712a3ef05392aa212c6b52db8817e1b626ccb1c0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 712a3ef Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild