always default syncdb to false

util/jenkins/check-migrations.sh

@@ -33,6 +33,10 @@ if [[ -f ${WORKSPACE}/configuration-secure/ansible/vars/${deployment}.yml ]]; th
     extra_var_args+=" -e@${WORKSPACE}/configuration-secure/ansible/vars/${deployment}.yml"
 fi
 
+if [[ -z $sync_db ]]; then
+    syncdb="false"
+fi
+
 if [[ $db_dry_run == "false" ]]; then
     # Set this to an empty string if db_dry_run is 
     # not set.  By default the db_dry_run var is