$ git clone -n https://src.fedoraproject.org/rpms/rust-fscommon.git /var/lib/mock/f45-build-41734-785/root/chroot_tmpdir/scmroot/rust-fscommon
Cloning into '/var/lib/mock/f45-build-41734-785/root/chroot_tmpdir/scmroot/rust-fscommon'...
$ git fetch origin 2b2ba4e411725968491bbf410b08082dd4c75376:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-fscommon
 * [new ref]         2b2ba4e411725968491bbf410b08082dd4c75376 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2b2ba4e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild