$ git clone -n https://src.fedoraproject.org/rpms/R-haven.git /var/lib/mock/f40-build-1944457-25177/root/chroot_tmpdir/scmroot/R-haven
Cloning into '/var/lib/mock/f40-build-1944457-25177/root/chroot_tmpdir/scmroot/R-haven'...
$ git fetch origin e3fc76e8d5d5871579125d4b02f8e7b2c3a9791e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-haven
 * [new ref]         e3fc76e8d5d5871579125d4b02f8e7b2c3a9791e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e3fc76e Update to latest version