pagerduty.py: Change default summary text (#4239)

* pagerduty.py: Change default summary text

Change is made to use alert name in PagerDuty's alert
destination default summary text instead of
query id and name

* Update default description text & field description

redash/destinations/pagerduty.py

@@ -12,7 +12,7 @@
 class PagerDuty(BaseDestination):
 
     KEY_STRING = '{alert_id}_{query_id}'
-    DESCRIPTION_STR = u'Alert - Redash Query #{query_id}: {query_name}'
+    DESCRIPTION_STR = u'Alert: {alert_name}'
 
     @classmethod
     def enabled(cls):
@@ -29,7 +29,7 @@ def configuration_schema(cls):
                 },
                 'description': {
                     'type': 'string',
-                    'title': 'Description for the event, defaults to query',
+                    'title': 'Description for the event, defaults to alert name',
                 }
             },
             "required": ["integration_key"]
@@ -46,7 +46,7 @@ def notify(self, alert, query, user, new_state, app, host, options):
         elif options.get('description'):
             default_desc = options.get('description')
         else:
-            default_desc = self.DESCRIPTION_STR.format(query_id=query.id, query_name=query.name)
+            default_desc = self.DESCRIPTION_STR.format(alert_name=alert.name)
 
         incident_key = self.KEY_STRING.format(alert_id=alert.id, query_id=query.id)
         data = {