[flake8-bandit] Fix correct example for S308 (#21128)

<!--
Thank you for contributing to Ruff/ty! To help us out with reviewing,
please consider the following:

- Does this pull request include a summary of the change? (See below.)
- Does this pull request include a descriptive title? (Please prefix
with `[ty]` for ty pull
  requests.)
- Does this pull request include references to any relevant issues?
-->

## Summary
Fixed the incorrect import example in the "correct exmaple"
<!-- What's the purpose of the change? What does it do, and why? -->

## Test Plan
🤷 
<!-- How was it tested? -->

crates/ruff_linter/src/rules/flake8_bandit/rules/suspicious_function_call.rs

@@ -375,7 +375,7 @@ impl Violation for SuspiciousEvalUsage {
 ///
 ///
 /// def render_username(username):
-///     return django.utils.html.format_html("<i>{}</i>", username)  # username is escaped.
+///     return format_html("<i>{}</i>", username)  # username is escaped.
 /// ```
 ///
 /// ## References