$ git clone -n https://src.fedoraproject.org/rpms/rust-fastrand1.git /var/lib/mock/f45-build-41592-784/root/chroot_tmpdir/scmroot/rust-fastrand1
Cloning into '/var/lib/mock/f45-build-41592-784/root/chroot_tmpdir/scmroot/rust-fastrand1'...
$ git fetch origin f02752e1003f6019e01c56959c3fb3c9d0af92f9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-fastrand1
 * [new ref]         f02752e1003f6019e01c56959c3fb3c9d0af92f9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f02752e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild