[AIRFLOW-2822] Fix HipChat Deprecation Warning
[AIRFLOW-2822] Fix HipChat Deprecation Warning

Fixes PendingDeprecationWarning on HipChatAPISendRoomNotificationOperator

Using `HipChatAPISendRoomNotificationOperator` on Airflow master branch (2.0) gives:

airflow/models.py:2390: PendingDeprecationWarning:
Invalid arguments were passed to HipChatAPISendRoomNotificationOperator.
Support for passing such arguments will be dropped in Airflow 2.0.
Invalid arguments were:
*args: ()
**kwargs: {'color': 'green'}
category=PendingDeprecationWarning

mrkm4ntr/incubator-airflow,malmiron/incubator-airflow,lyft/incubator-airflow,apache/airflow,dhuang/incubator-airflow,gtoonstra/airflow,cfei18/incubator-airflow,sekikn/incubator-airflow,artwr/airflow,danielvdende/incubator-airflow,r39132/airflow,akosel/incubator-airflow,Fokko/incubator-airflow,apache/incubator-airflow,apache/airflow,malmiron/incubator-airflow,andyxhadji/incubator-airflow,DinoCow/airflow,spektom/incubator-airflow,DinoCow/airflow,dhuang/incubator-airflow,jgao54/airflow,mrkm4ntr/incubator-airflow,lyft/incubator-airflow,andyxhadji/incubator-airflow,apache/incubator-airflow,wileeam/airflow,adamhaney/airflow,spektom/incubator-airflow,apache/incubator-airflow,artwr/airflow,sid88in/incubator-airflow,bolkedebruin/airflow,cfei18/incubator-airflow,mistercrunch/airflow,lyft/incubator-airflow,wileeam/airflow,sekikn/incubator-airflow,nathanielvarona/airflow,mistercrunch/airflow,jgao54/airflow,adamhaney/airflow,andyxhadji/incubator-airflow,cfei18/incubator-airflow,wooga/airflow,DinoCow/airflow,bolkedebruin/airflow,sid88in/incubator-airflow,criccomini/airflow,r39132/airflow,apache/airflow,Fokko/incubator-airflow,fenglu-g/incubator-airflow,fenglu-g/incubator-airflow,gtoonstra/airflow,airbnb/airflow,danielvdende/incubator-airflow,bolkedebruin/airflow,jgao54/airflow,sekikn/incubator-airflow,Fokko/incubator-airflow,edgarRd/incubator-airflow,mrkm4ntr/incubator-airflow,Acehaidrey/incubator-airflow,edgarRd/incubator-airflow,sid88in/incubator-airflow,adamhaney/airflow,malmiron/incubator-airflow,jgao54/airflow,apache/incubator-airflow,wileeam/airflow,nathanielvarona/airflow,spektom/incubator-airflow,lyft/incubator-airflow,danielvdende/incubator-airflow,Acehaidrey/incubator-airflow,akosel/incubator-airflow,adamhaney/airflow,airbnb/airflow,andyxhadji/incubator-airflow,mistercrunch/airflow,akosel/incubator-airflow,artwr/airflow,mtagle/airflow,criccomini/airflow,cfei18/incubator-airflow,apache/airflow,bolkedebruin/airflow,mtagle/airflow,nathanielvarona/airflow,artwr/airflow,nathanielvarona/airflow,nathanielvarona/airflow,wooga/airflow,apache/airflow,danielvdende/incubator-airflow,apache/airflow,criccomini/airflow,r39132/airflow,akosel/incubator-airflow,edgarRd/incubator-airflow,r39132/airflow,wooga/airflow,danielvdende/incubator-airflow,mtagle/airflow,mtagle/airflow,DinoCow/airflow,criccomini/airflow,cfei18/incubator-airflow,airbnb/airflow,gtoonstra/airflow,sid88in/incubator-airflow,malmiron/incubator-airflow,dhuang/incubator-airflow,airbnb/airflow,bolkedebruin/airflow,fenglu-g/incubator-airflow,gtoonstra/airflow,Acehaidrey/incubator-airflow,Fokko/incubator-airflow,fenglu-g/incubator-airflow,Acehaidrey/incubator-airflow,mrkm4ntr/incubator-airflow,Acehaidrey/incubator-airflow,danielvdende/incubator-airflow,wooga/airflow,dhuang/incubator-airflow,edgarRd/incubator-airflow,cfei18/incubator-airflow,Acehaidrey/incubator-airflow,mistercrunch/airflow,sekikn/incubator-airflow,spektom/incubator-airflow,nathanielvarona/airflow,wileeam/airflow