[`flake8-annotations`] Remove unused import in example (`ANN401`) (#20000)

## Summary

Remove unused import in the  "Use instead" example.

## Test Plan

It's just a text description, no test needed

crates/ruff_linter/src/rules/flake8_annotations/rules/definition.rs

@@ -485,9 +485,6 @@ impl Violation for MissingReturnTypeClassMethod {
 /// Use instead:
 ///
 /// ```python
-/// from typing import Any
-///
-///
 /// def foo(x: int): ...
 /// ```
 ///