fix(api-client): Fixed api client to handle graphql errors

custom_components/octopus_energy/api_client.py

@@ -833,7 +833,15 @@ async def __async_read_response__(self, response, url):
         raise RequestError(msg)
       return None
 
+    data_as_json = None
     try:
-      return json.loads(text)
+      data_as_json = json.loads(text)
     except:
       raise Exception(f'Failed to extract response json: {url}; {text}')
+
+    if ("graphql" in url and "errors" in data_as_json):
+      msg = f'Errors in request ({url}): {data_as_json["errors"]}'
+      _LOGGER.debug(msg)
+      raise RequestError(msg)
+
+    return data_as_json