Revert "reserve bottom space for error message (#3446)"

This reverts commit d405d0d3930876bcbc66a727a91393a06e90be18.

nicegui/elements/mixins/validation_element.py

@@ -12,7 +12,6 @@ class ValidationElement(ValueElement):
         self._auto_validation = True
         self._error: Optional[str] = None
         super().__init__(**kwargs)
-        self._props['error'] = False  # NOTE: reserve bottom space for error message
 
     @property
     def error(self) -> Optional[str]: