Fix typo in Dialogflow QueryResult
Fix typo in Dialogflow QueryResult

In dialogflow's interface 'QueryResult' languageCode was misspelled incorrectly
AgentME/DefinitelyTyped,magny/DefinitelyTyped,borisyankov/DefinitelyTyped,AgentME/DefinitelyTyped,AgentME/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,markogresak/DefinitelyTyped,dsebastien/DefinitelyTyped,magny/DefinitelyTyped,georgemarshall/DefinitelyTyped,mcliment/DefinitelyTyped,AgentME/DefinitelyTyped