Consider a data type failsafe

[pnadolny13]

Although its a good practice for the tap to fully map all json properties, it would be awesome if the target could have a fail safe data type like String when the exact data type cant be found. The recent case is someone trying to load tap snapchat which has some empty properties for the creatives and campaigns streams. Right now the target fails, but ideally it would succeed with maybe a warning and just write String (or equivalent) data.

This data type failsafe was proposed as an item to be added as a best practice to the Singer ecosystem MeltanoLabs/Singer-Working-Group#20.

[gnilrets]

+1

I ran into this issue today building my first tap. Worked great with jsonl, but then failed when I tried running it with this bigquery target.