[AIRFLOW-3241] Remove Invalid template ext in GCS Sensors (#4076)
[AIRFLOW-3241] Remove Invalid template ext in GCS Sensors (#4076)

- Remove `template_ext = ('.sql',)`
- Fix Docstrings (Incorrect connection name and indentation)
Acehaidrey/incubator-airflow,jgao54/airflow,Acehaidrey/incubator-airflow,nathanielvarona/airflow,apache/incubator-airflow,lyft/incubator-airflow,dhuang/incubator-airflow,apache/incubator-airflow,apache/incubator-airflow,adamhaney/airflow,spektom/incubator-airflow,mistercrunch/airflow,nathanielvarona/airflow,nathanielvarona/airflow,wooga/airflow,sekikn/incubator-airflow,wileeam/airflow,r39132/airflow,fenglu-g/incubator-airflow,cfei18/incubator-airflow,DinoCow/airflow,Acehaidrey/incubator-airflow,apache/airflow,danielvdende/incubator-airflow,sekikn/incubator-airflow,nathanielvarona/airflow,danielvdende/incubator-airflow,apache/airflow,apache/airflow,r39132/airflow,cfei18/incubator-airflow,danielvdende/incubator-airflow,mistercrunch/airflow,apache/airflow,danielvdende/incubator-airflow,cfei18/incubator-airflow,adamhaney/airflow,wooga/airflow,artwr/airflow,mrkm4ntr/incubator-airflow,cfei18/incubator-airflow,Fokko/incubator-airflow,cfei18/incubator-airflow,lyft/incubator-airflow,wooga/airflow,dhuang/incubator-airflow,fenglu-g/incubator-airflow,artwr/airflow,fenglu-g/incubator-airflow,wileeam/airflow,malmiron/incubator-airflow,sekikn/incubator-airflow,r39132/airflow,sekikn/incubator-airflow,cfei18/incubator-airflow,wileeam/airflow,airbnb/airflow,apache/airflow,Acehaidrey/incubator-airflow,malmiron/incubator-airflow,bolkedebruin/airflow,spektom/incubator-airflow,mistercrunch/airflow,artwr/airflow,mtagle/airflow,bolkedebruin/airflow,apache/airflow,r39132/airflow,danielvdende/incubator-airflow,artwr/airflow,mtagle/airflow,lyft/incubator-airflow,bolkedebruin/airflow,mistercrunch/airflow,mtagle/airflow,spektom/incubator-airflow,mrkm4ntr/incubator-airflow,apache/incubator-airflow,fenglu-g/incubator-airflow,DinoCow/airflow,DinoCow/airflow,Acehaidrey/incubator-airflow,wooga/airflow,jgao54/airflow,airbnb/airflow,adamhaney/airflow,dhuang/incubator-airflow,nathanielvarona/airflow,dhuang/incubator-airflow,bolkedebruin/airflow,spektom/incubator-airflow,lyft/incubator-airflow,jgao54/airflow,mtagle/airflow,mrkm4ntr/incubator-airflow,nathanielvarona/airflow,Fokko/incubator-airflow,Fokko/incubator-airflow,Fokko/incubator-airflow,Acehaidrey/incubator-airflow,malmiron/incubator-airflow,malmiron/incubator-airflow,wileeam/airflow,DinoCow/airflow,airbnb/airflow,danielvdende/incubator-airflow,airbnb/airflow,jgao54/airflow,bolkedebruin/airflow,adamhaney/airflow,mrkm4ntr/incubator-airflow