Add version check for urllib3 in backoff calculation (#526)

Signed-off-by: Shivam Raj <shivam.raj@databricks.com>
Signed-off-by: varun-edachali-dbx <varun.edachali@databricks.com>

Author: shivam2680

src/databricks/sql/auth/retry.py

@@ -17,6 +17,8 @@
     from urllib3 import HTTPResponse as BaseHTTPResponse
 from urllib3 import Retry
 from urllib3.util.retry import RequestHistory
+from packaging import version
+
 
 
 from databricks.sql.exc import (