Add a worker for backfilling labels on manifests that have already been backfilled

conf/init/service/batch/labelbackfillworker/log/run

@@ -0,0 +1,4 @@
+#!/bin/sh
+
+# Start the logger
+exec logger -i -t labelbackfillworker

conf/init/service/batch/labelbackfillworker/run

@@ -0,0 +1,9 @@
+#! /bin/bash
+
+echo 'Starting label backfill worker'
+
+QUAYPATH=${QUAYPATH:-"."}
+cd ${QUAYDIR:-"/"}
+PYTHONPATH=$QUAYPATH venv/bin/python -m workers.labelbackfillworker 2>&1
+
+echo 'Repository label backfill exited'