feat: ensure supercronic only loads the crontab once when the entrypo…

…int is called multiple times during startup

pact_broker/entrypoint.sh

@@ -1,8 +1,9 @@
 #!/bin/sh
 
-if [ "${PACT_BROKER_DATABASE_BETA_CLEAN_ENABLED}" = "true" ]; then
+if [ "${PACT_BROKER_DATABASE_BETA_CLEAN_ENABLED}" = "true" ] && [ ! -f .supercronic ]; then
   echo "Creating crontab with schedule ${PACT_BROKER_DATABASE_CLEAN_CRON_SCHEDULE} to clean database"
   echo "${PACT_BROKER_DATABASE_CLEAN_CRON_SCHEDULE} /pact_broker/clean.sh" >> /pact_broker/crontab
+  touch .supercronic
   /usr/local/bin/supercronic -quiet -passthrough-logs /pact_broker/crontab &
 fi