Clean up pre GHES 3.14 code paths

[henrymercer]

A small cleanup, but I think still worth it.

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?

Workflow types:

• Advanced setup - Impacts users who have custom CodeQL workflows.
• Managed - Impacts users with dynamic workflows (Default Setup, Code Quality, ...).

Products:

• Code Scanning - The changes impact analyses when analysis-kinds: code-scanning.
• Code Quality - The changes impact analyses when analysis-kinds: code-quality.
• Other first-party - The changes impact other first-party analyses.
• Third-party analyses - The changes affect the upload-sarif action.

Environments:

• GHES - Impacts CodeQL workflows on 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.

Are there any special considerations for merging or releasing this change?

• No special considerations - This change can be merged at any time.

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.

[Copilot]

Pull request overview

This PR removes code paths and tests specific to GHES versions earlier than 3.14, simplifying behavior around SARIF merge deprecation warnings and minor telemetry comment cleanup.

Changes:

• Simplifies shouldShowCombineSarifFilesDeprecationWarning to no longer depend on the GitHub version (removes pre-3.14 GHES special-casing).
• Updates unit tests to match the simplified warning behavior and removes GHES 3.13-specific test cases.
• Removes an outdated comment about RUNNER_ARCH availability.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/upload-lib.ts	Removes pre-GHES-3.14 branching for the SARIF merge deprecation warning and updates call sites.
src/upload-lib.test.ts	Updates tests for the changed warning API and drops GHES 3.13-specific expectations.
src/status-report.ts	Removes an outdated GHES-version-specific comment while retaining the env-var presence guard.
lib/upload-sarif-action.js	Generated output reflecting src/ changes.
lib/upload-lib.js	Generated output reflecting src/ changes.
lib/init-action-post.js	Generated output reflecting src/ changes.
lib/analyze-action.js	Generated output reflecting src/ changes.