Regenerate dialogflow client (#5892)

Author: yoshi-automation

google-api-grpc/proto-google-cloud-dialogflow-v2/src/main/java/com/google/cloud/dialogflow/v2/QueryResult.java

@@ -244,7 +244,7 @@ message QueryResult {
 
   // The intent that matched the conversational query. Some, not
   // all fields are filled in this message, including but not limited to:
-  // `name`, `display_name` and `webhook_state`.
+  // `name`, `display_name`, `end_interaction` and `is_fallback`.
   Intent intent = 11;
 
   // The intent detection confidence. Values range from 0.0