$ git clone -n https://src.fedoraproject.org/rpms/rust-invalidstring.git /var/lib/mock/f45-build-42615-795/root/chroot_tmpdir/scmroot/rust-invalidstring
Cloning into '/var/lib/mock/f45-build-42615-795/root/chroot_tmpdir/scmroot/rust-invalidstring'...
$ git fetch origin 693781bffa3288628c2a250a711883d849d2f7b7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-invalidstring
 * [new ref]         693781bffa3288628c2a250a711883d849d2f7b7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 693781b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild