$ git clone -n https://src.fedoraproject.org/rpms/nss.git /var/lib/mock/f41-build-861221-169528/root/chroot_tmpdir/scmroot/nss
Cloning into '/var/lib/mock/f41-build-861221-169528/root/chroot_tmpdir/scmroot/nss'...
$ git fetch origin 1b792e8970f0e2a01f6a47db79346317ad8d2e9b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/nss
 * [new ref]         1b792e8970f0e2a01f6a47db79346317ad8d2e9b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1b792e8 Update NSS to 3.105.0