$ git clone -n https://src.fedoraproject.org/rpms/rust-serial_test.git /var/lib/mock/f38-build-side-42-init-devel-1146959-30463/root/chroot_tmpdir/scmroot/rust-serial_test
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1146959-30463/root/chroot_tmpdir/scmroot/rust-serial_test'...
$ git fetch origin cc2dc8e424e2861a8bf9a218c20d0a4fe48ca26d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-serial_test
 * [new ref]         cc2dc8e424e2861a8bf9a218c20d0a4fe48ca26d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cc2dc8e Update to version 2.0.0; Fixes RHBZ#2183043