Fix an exception, container env must be a list

Author: philippemerle

bin/kube-diagrams

@@ -532,7 +532,10 @@ class EdgesContext(list):
             return
         target_resources = set()
         for container in containers:
-            for env in query_path(container, "env", []):
+            container_env = query_path(container, "env")
+            if not isinstance(container_env, list):
+                continue # skip this container when env is not a list!
+            for env in container_env:
                 config_map_key_ref_name = query_path(env, "valueFrom.configMapKeyRef.name")
                 if config_map_key_ref_name is not None:
                     target_resources.add(