Delete instead of truncate (#143)

* Change truncate to delete for QoS rules reset

* fix

cads_broker/database.py

@@ -372,7 +372,7 @@ def get_events_from_request(
 
 def reset_qos_rules(session: sa.orm.Session, qos):
     """Delete all QoS rules."""
-    session.execute(sa.text("truncate qos_rules cascade"))
+    session.execute(sa.text("delete from qos_rules cascade"))
     # for rule in session.scalars(sa.select(QoSRule)):
     #     # rule.system_requests = []
     #     session.delete(rule)