Handle case of 0 connect retries better

With a default of 0 connect_retries, confusing log messages show up.
The logs suggest that a retry is going to be carried out, but it isn't.
Also, a sleep is carried out, even if no retries are to happen. This
check prevents this from happening.

Author: danielvdende

dbt/adapters/spark/connections.py

@@ -401,7 +401,7 @@ def open(cls, connection):
                         msg += ', is your token valid?'
                     raise dbt.exceptions.FailedToConnectException(msg) from e
                 retryable_message = _is_retryable_error(e)
-                if retryable_message:
+                if retryable_message and creds.connect_retries > 0:
                     msg = (
                         f"Warning: {retryable_message}\n\tRetrying in "
                         f"{creds.connect_timeout} seconds "