PIE810 autofix changes raw strings to backslashes

Start with this code:

```python
if x.startswith("a") or x.startswith("b") or re.match(r"a\.b", x):
    pass
```

Ruff correctly complains that I should use a single `.startswith()` call.

Run Ruff's autofix for PIE810:

```python
if x.startswith(("a", "b")) or re.match("a\\.b", x):
    pass
```

And now my string is not raw any more.