$ git clone -n https://src.fedoraproject.org/rpms/rust-test-tag.git /var/lib/mock/f45-build-45398-822/root/chroot_tmpdir/scmroot/rust-test-tag
Cloning into '/var/lib/mock/f45-build-45398-822/root/chroot_tmpdir/scmroot/rust-test-tag'...
$ git fetch origin f442cd2e728a17e933d4eae90ecc279c869de516:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-test-tag
 * [new ref]         f442cd2e728a17e933d4eae90ecc279c869de516 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f442cd2 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild