Merge pull request #7531 from pmorie/secret-docs

Fix representation of v1beta3 pod in secrets doc

docs/secrets.md

@@ -48,11 +48,9 @@ This is an example of a pod that uses a secret, in json format:
       }],
       "volumes": [{
         "name": "foo",
-        "source": {
         "secret": {
           "secretName": "mysecret"
         }
-        }
       }]
     }
   }