chore(ruff): apply formatting and integrate into CI

[johubertj]

Resolved issues:

resolves #5027

Description of changes:

• Reformatted all tests/integrationv2 files using ruff
• Replaced autopep8 with ruff as the default formatter in CI (ci_linting.yml).

Manual changes:

• Replaced autopep8 with ruff in ci_linting.yml.

Automated changes:

• Used uv run ruff format to format all files in tests/integrationv2.

Why replace autopep8 with ruff?

• Ruff provides a rustfmt-like experience, meaning it enforces a standardized, opinionated code style with minimal configuration. Unlike autopep8, which primarily focuses on fixing formatting issues, ruff operates with a "set it and forget it" approach—developers do not need to fine-tune settings or make repeated manual fixes to satisfy linting rules.
• Unlike autopep8, which only handles formatting, ruff also functions as a linter and static analysis tool, reducing the need for multiple dependencies.
• Ruff is significantly faster than autopep8, improving efficiency in both local development and CI runs.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[github-advanced-security]

CodeQL found more than 20 potential problems in the proposed changes. Check the Files changed tab for more details.

[jmayclin]

Looks good! But for the sake of documentation, we probably want to add some context to the PR description.

• What changes are done manually?
• What changes were automated?
  • What command was used to make the automated changes?
• Why is this change being made? Why replace pep8?

[dougch]

Such consistency...nice.
minor nit: can you also cleanup the pep8 config? https://github.com/aws/s2n-tls/blob/main/.pep8