Update deprecation warnings for CodeQL Action to v4

[mario-campos]

Risk assessment

For internal use only. Please select the risk level of this change:

• Low risk: Changes are fully under feature flags, or have been fully tested and validated in pre-production environments and are highly observable, or are documentation or test only.

Which use cases does this change impact?

• Advanced setup - Impacts users who have custom workflows.
• GHES - Impacts GitHub Enterprise Server.

How did/will you validate this change?

• Unit tests - I am depending on unit test coverage (i.e. tests in .test.ts files).
• End-to-end tests - I am depending on PR checks (i.e. tests in pr-checks).

If something goes wrong after this change is released, what are the mitigation and rollback strategies?

• Rollback - Change can only be disabled by rolling back the release or releasing a new version with a fix.

How will you know if something goes wrong after this change is released?

• Telemetry - I rely on existing telemetry or have made changes to the telemetry.
  • Alerts - New or existing monitors will trip if something goes wrong with this change.
• Other - Feedback

Merge / deployment checklist

• Confirm this change is backwards compatible with existing workflows.
• Consider adding a changelog entry for this change.
• Confirm the readme and docs have been updated if necessary.

[mario-campos]

@henrymercer, could you review this PR? I've got some failing checks and I'm honestly stumped—Copilot wasn't much help either.

util › checkActionVersion reports error for CodeQL Action version 2.2.1 and GitHub version GHES 3.11
...
util › checkActionVersion reports error for CodeQL Action version 2.2.1 and GitHub version GHES 3.12

It seems to consistently fail for these two sets of versions 🤔

Edit: Nevermind

[Copilot]

Pull Request Overview

This PR updates the CodeQL Action version deprecation warning from v3 to v4. The changes prepare users for the upcoming deprecation of CodeQL Action v3 by updating version checks, error messages, and minimum supported GHES version requirements.

• Updates version check logic to warn users running v1, v2, or v3 to upgrade to v4
• Changes minimum GHES version requirement from 3.11 to 3.20 for v4 support
• Updates deprecation message and changelog URL

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

File	Description
src/util.ts	Updated checkActionVersion function to check for v4 instead of v3, changed GHES minimum version to 3.20, and updated deprecation message
src/util.test.ts	Added test cases for v3 and v4 version checks with various GHES versions, updated expected error message
lib/*.js	Generated JavaScript files reflecting the TypeScript changes (auto-generated, not reviewed per guidelines)
CHANGELOG.md	Documented the new v3 to v4 migration warning