[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

docs/migration_guide.md

@@ -70,7 +70,7 @@ _Migration steps_
    ```python
    # Old
    agent = MyAgent(self.next_id(), self, ...)
-   
+
    # New
    agent = MyAgent(self, ...)
    ```