[bug] Add missing group property to the Account model (#3746)

* Stub out account's Group parameter

* Fix typo in Contributing documentation

* Update swagger and match style

* Update the swagger command to mimic test/swagger.sh

* Fix tests for new `group` param in Account model

* More test changes for new `group` param in Account

* Continuing test changes for `group` param stubbing

* Another round of `group` stubbing for tests

internal/processing/stream/notification_test.go

@@ -82,7 +82,8 @@ func (suite *NotificationTestSuite) TestStreamNotification() {
     "statuses_count": 4,
     "last_status_at": "2024-11-01",
     "emojis": [],
-    "fields": []
+    "fields": [],
+    "group": false
   }
 }`, dst.String())
 }