PEP 750 changes do no guard for usage with older versions like `ast.parse(t'', feature_version=(3, 13))`

# Bug report

Example:

```python
>>> code = 't""'
>>> import ast
>>> ast.parse(code, feature_version=(3, 8))
Module(body=[Expr(value=TemplateStr(values=[]))], type_ignores=[])
```

I would like to work on the fix.


### Linked PRs
* gh-133202
* gh-133225