$ git clone -n https://src.fedoraproject.org/rpms/rust-os_str_bytes.git /var/lib/mock/f45-build-43594-804/root/chroot_tmpdir/scmroot/rust-os_str_bytes
Cloning into '/var/lib/mock/f45-build-43594-804/root/chroot_tmpdir/scmroot/rust-os_str_bytes'...
$ git fetch origin 9e51e5785642639b32c58980cb033299b595bba7:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-os_str_bytes
 * [new ref]         9e51e5785642639b32c58980cb033299b595bba7 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9e51e57 Update to version 7.2.1; Fixes RHBZ#2464677