Fix null scenario

Author: jeffersoncasimir

modules/dqt/php/module.class.inc

@@ -86,7 +86,7 @@ class Module extends \Module
                   JOIN cached_data_type USING (CachedDataTypeID)
                   WHERE Name='projects_disk_space'",
                         []
-                    )
+                    ) ?? ''
                 ),
                 true
             );

modules/statistics/php/widgets.class.inc

@@ -129,7 +129,7 @@ class Widgets extends \NDB_Page implements ETagCalculator
                   JOIN cached_data_type USING (CachedDataTypeID)
                   WHERE Name='projects_disk_space'",
                     []
-                )
+                ) ?? ''
             ),
             true
         );