$ git clone -n https://src.fedoraproject.org/rpms/rust-matchit.git /var/lib/mock/f45-build-43140-800/root/chroot_tmpdir/scmroot/rust-matchit
Cloning into '/var/lib/mock/f45-build-43140-800/root/chroot_tmpdir/scmroot/rust-matchit'...
$ git fetch origin b91cff4ca240740a490b612082a8c97577ac680f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-matchit
 * [new ref]         b91cff4ca240740a490b612082a8c97577ac680f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b91cff4 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild