[pyupgrade] Make example error out-of-the-box (UP041) (#19292)

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## Summary

<!-- What's the purpose of the change? What does it do, and why? -->

Part of #18972

This PR makes [timeout-error-alias
(UP041)](https://docs.astral.sh/ruff/rules/timeout-error-alias/#timeout-error-alias-up041)'s
example error out-of-the-box.

[Old example](https://play.ruff.rs/87e20352-d80a-46ec-98a2-6f6ea700438b)
```py
raise asyncio.TimeoutError
```

[New example](https://play.ruff.rs/d3b95557-46a2-4856-bd71-30d5f3f5ca44)
```py
import asyncio

raise asyncio.TimeoutError
```

## Test Plan

<!-- How was it tested? -->

N/A, no functionality/tests affected

Author: MeGaGiGaGon

crates/ruff_linter/src/rules/pyupgrade/rules/timeout_error_alias.rs

@@ -27,6 +27,8 @@ use crate::{AlwaysFixableViolation, Edit, Fix};
 ///
 /// ## Example
 /// ```python
+/// import asyncio
+///
 /// raise asyncio.TimeoutError
 /// ```
 ///