added comment for RLock

Signed-off-by: Sai Shree Pradhan <saishree.pradhan@databricks.com>

Author: saishreeeee

src/databricks/sql/telemetry/telemetry_client.py

@@ -317,6 +317,7 @@ class TelemetryClientFactory:
     _executor: Optional[ThreadPoolExecutor] = None
     _initialized: bool = False
     _lock = threading.RLock()  # Thread safety for factory operations
+    # used RLock instead of Lock to avoid deadlocks when garbage collection is triggered
     _original_excepthook = None
     _excepthook_installed = False