[Crowdin] string fix + misc. typo and whitespace fixes

* Crowdin link: https://crowdin.com/translate/freecad/6766/en-hu#6576162  
* Tacked on a few typo+whitespace fixes

src/Mod/Material/MaterialEditor.py

@@ -682,7 +682,7 @@ def editMaterial(material=None, card_path=None):
     if result:
         return editor.getDict()
     else:
-        # on chancel button an empty dict is returned
+        # on cancel button an empty dict is returned
         return {}