Using `near create-account sponsor-by-faucet-service` errors out

[shariffdev]

https://helper.nearprotocol.com responded with status 503 when using the near account create-account sponsor-by-faucet-service command.

Add helpful message for this scenario instead of what is dumped:

Error: 
   0: error decoding response body: expected value at line 1 column 1
   1: expected value at line 1 column 1