Allow exec and function transformers to generate resources

plugin/someteam.example.com/v1/starlarkmixer/StarlarkMixer_test.go

@@ -38,12 +38,24 @@ data:
 kind: ConfigMap
 metadata:
   annotations:
+    config.kubernetes.io/path: configmap_some-cm.yaml
     modified-by: mixer-instance
   name: some-cm
 ---
 apiVersion: v1
+data:
+  foo: bar
 kind: ConfigMap
 metadata:
+  annotations:
+    config.kubernetes.io/path: configmap_some-cm-copy.yaml
+  name: some-cm-copy
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  annotations:
+    config.kubernetes.io/path: configmap_net-new.yaml
   name: net-new
 `)
 }