Remove the @slot decorator of plugins.editor.Editor.new(). Fix spyder…

…-ide#3186

The original `@Slot()` decorator of `Editor.new(self, fname, ...)` ignores the
`fname` argument which is passed in when creating a new module with a given
name (e.g., through context menu "New -> Module..." in Project explorer).
The correct decorator should be `@Slot(str)`, which can also be ignored
completely since a Qt Signal can connect to a plain Python callable.

spyderlib/plugins/editor.py

@@ -1521,7 +1521,7 @@ def _clone_file_everywhere(self, finfo):
             editor = editorstack.clone_editor_from(finfo, set_current=False)
             self.register_widget_shortcuts("Editor", editor)
 
-    @Slot()
+#    @Slot(str)
     def new(self, fname=None, editorstack=None, text=None):
         """
         Create a new file - Untitled