memo: Fix default response model docs
Fix a discrepancy in the `tax` parameters default value between the docs
and the code example.
@@ -93,7 +93,7 @@ Your response model could have default values, like:
```
* `description: str = None` has a default of `None`.
-* `tax: float = None` has a default of `None`.
+* `tax: float = 10.5` has a default of `10.5`.
* `tags: List[str] = []` has a default of an empty list: `[]`.
but you might want to omit them from the result if they were not actually stored.
