message: add 'description' to Relation
diff: @@ -144,6 +144,8 @@ class DuckDBPyRelation:
  @property
  def columns(self) -> list: ...
  @property
  + def description(self) -> list: ...
  + @property
  def dtypes(self) -> list: ...
  @property
  def shape(self) -> tuple: ...
  