PLT-7619: Cleanup flags in data retention. (#7501)

store/store.go

@@ -346,6 +346,7 @@ type PreferenceStore interface {
 	DeleteCategoryAndName(category string, name string) StoreChannel
 	PermanentDeleteByUser(userId string) StoreChannel
 	IsFeatureEnabled(feature, userId string) StoreChannel
+	CleanupFlagsBatch(limit int64) StoreChannel
 }
 
 type LicenseStore interface {