Fixed expected test data

Author: gerdos82

internal/controller/mapserver/test_data/expected_volumemounts.yaml

@@ -1,6 +1,7 @@
 volumeMounts:
 - mountPath: /srv/data
   name: base
+  readOnly: true
 - mountPath: /var/www
   name: data
 - mountPath: /srv/mapserver/config/include.conf