$ git clone -n https://src.fedoraproject.org/rpms/rust-cairo-rs.git /var/lib/mock/f39-build-2251452-54112/root/chroot_tmpdir/scmroot/rust-cairo-rs
Cloning into '/var/lib/mock/f39-build-2251452-54112/root/chroot_tmpdir/scmroot/rust-cairo-rs'...
$ git fetch origin 773c6b212b2bba9d75b84cab4b53f412b26eddd6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cairo-rs
 * [new ref]         773c6b212b2bba9d75b84cab4b53f412b26eddd6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 773c6b2 Update to version 0.18.5; Fixes RHBZ#2247765