Fix missing requird in benchmark crd

This MR marks appResource, loadGenResource, resourceTypes, loadTypes, kafkaConfig as required for all custom resources with kind benchmark

theodolite/crd/crd-benchmark.yaml

@@ -20,7 +20,7 @@ spec:
         properties:
           spec:
             type: object
-            required: []
+            required: ["appResource", "loadGenResource", "resourceTypes", "loadTypes", "kafkaConfig"]
             properties:
               name:
                 type: string