$ git clone -n https://src.fedoraproject.org/rpms/rust-drop-tracker.git /var/lib/mock/f45-build-41409-782/root/chroot_tmpdir/scmroot/rust-drop-tracker
Cloning into '/var/lib/mock/f45-build-41409-782/root/chroot_tmpdir/scmroot/rust-drop-tracker'...
$ git fetch origin b1c89f92975bb72d5f3bab4189edb81db177ff8e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-drop-tracker
 * [new ref]         b1c89f92975bb72d5f3bab4189edb81db177ff8e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1c89f9 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild