$ git clone -n https://src.fedoraproject.org/rpms/rust-osmesa-sys.git /var/lib/mock/f41-build-725172-13118/root/chroot_tmpdir/scmroot/rust-osmesa-sys
Cloning into '/var/lib/mock/f41-build-725172-13118/root/chroot_tmpdir/scmroot/rust-osmesa-sys'...
$ git fetch origin 21cee1d74e07f6d3f7c8705fdb3077dc6f2f2a86:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-osmesa-sys
 * [new ref]         21cee1d74e07f6d3f7c8705fdb3077dc6f2f2a86 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 21cee1d unused leaf package for more than two release cycles