[MM-16751] golint model (#17896)

store/sqlstore/session_store.go

@@ -283,7 +283,7 @@ func (me SqlSessionStore) Cleanup(expiryTime int64, batchSize int64) {
 	mlog.Debug("Cleaning up session store.")
 
 	var query string
-	if me.DriverName() == model.DATABASE_DRIVER_POSTGRES {
+	if me.DriverName() == model.DatabaseDriverPostgres {
 		query = "DELETE FROM Sessions WHERE Id = any (array (SELECT Id FROM Sessions WHERE ExpiresAt != 0 AND :ExpiresAt > ExpiresAt LIMIT :Limit))"
 	} else {
 		query = "DELETE FROM Sessions WHERE ExpiresAt != 0 AND :ExpiresAt > ExpiresAt LIMIT :Limit"