$ git clone -n https://src.fedoraproject.org/rpms/R-pkgload.git /var/lib/mock/f39-build-1536725-36340/root/chroot_tmpdir/scmroot/R-pkgload
Cloning into '/var/lib/mock/f39-build-1536725-36340/root/chroot_tmpdir/scmroot/R-pkgload'...
$ git fetch origin 661da401c5ca3d6d02eb5dc6ced27a8e381f183c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-pkgload
 * [new ref]         661da401c5ca3d6d02eb5dc6ced27a8e381f183c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 661da40 Update to 1.3.3