[flake8-builtins] Remove builtins- prefix from option names

[InSyncWithFoo]

Summary

Resolves #15368.

The following options have been renamed:

• builtins-allowed-modules → allowed-modules
• builtins-ignorelist → ignorelist
• builtins-strict-checking → strict-checking

To preserve compatibility, the old names are kept as Serde aliases.

Test Plan

cargo nextest run and cargo insta test.

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[MichaReiser]

Thanks. I think the builtins-ignorelist and builtins-allowed-modules in the summary are incorrect.

What we did in the past is to emit a deprecation warning for renamed settings so that we can remove the old names at some point in the future. It probably requires duplicating the fields on the Options structs and adding some custom code in Settings::from_options (I think it's called). Would you mind looking into this?

[dhruvmanila]

As an additional reference, I think the infrastructure already exists and lint.extend-ignore is an example of a deprecated setting.

[dhruvmanila]

Looks good