$ git clone -n https://src.fedoraproject.org/rpms/rust-sval_ref.git /var/lib/mock/f39-build-2081913-49799/root/chroot_tmpdir/scmroot/rust-sval_ref
Cloning into '/var/lib/mock/f39-build-2081913-49799/root/chroot_tmpdir/scmroot/rust-sval_ref'...
$ git fetch origin 1ccfc58fc5f2b018ae820f4b375e251f1c62ad0e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-sval_ref
 * [new ref]         1ccfc58fc5f2b018ae820f4b375e251f1c62ad0e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1ccfc58 Update to version 2.10.2; Fixes RHBZ#2239958