$ git clone -n https://src.fedoraproject.org/rpms/rust-unicode-segmentation.git /var/lib/mock/f45-build-45903-829/root/chroot_tmpdir/scmroot/rust-unicode-segmentation
Cloning into '/var/lib/mock/f45-build-45903-829/root/chroot_tmpdir/scmroot/rust-unicode-segmentation'...
$ git fetch origin b9ca9b77a3bfbc32f488b82545af39c7238dd78d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-unicode-segmentation
 * [new ref]         b9ca9b77a3bfbc32f488b82545af39c7238dd78d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b9ca9b7 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild