Fix feature tests for the database versions 11, 12 and 13, broken due to multirange data types support.

web/regression/feature_tests/pg_datatype_validation_test.py

@@ -190,6 +190,8 @@ class PGDataypeFeatureTest(BaseFeatureTest):
         self._create_enum_type()
         for batch in config_data:
             query = self.construct_select_query(batch)
+            if not query:
+                continue
             self.page.execute_query(query)
             wait = WebDriverWait(self.page.driver, 5)
 
@@ -266,7 +268,8 @@ class PGDataypeFeatureTest(BaseFeatureTest):
             else:
                 query += ',' + dataformatter.format(inputdata, datatype)
             first = False
-        return query + ';'
+        query = '' if query == 'SELECT ' else query + ';'
+        return query
 
     @staticmethod
     def check_result(datatype, source_code, string_to_find):