Backport of docs: Migrate link formats into stable-website

[vagrant-bot]

Backport

This PR is auto-generated from #13048 to be assessed for backporting due to the inclusion of the label backport/website.

The below text is copied from the body of the original PR.

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What

• Migrates the formats of links in Markdown content as part of the Docs Content Link Rewrites project
• Adds two new GitHub workflow files:
  • .github/workflows/check-legacy-links-format.yml - This is a workflow that checks if links in markdown content are in the new format. It does this by running the link rewrite script from dev-portal, and then asserting that no "rewriteable" links were found. This workflow will be used on subsequent PRs to maintain the new link format.
  • .github/workflows/test-link-rewrites.yml - This is a workflow that executes e2e tests of this PR's changes against the main branch's deploy preview. The tests only run for branches named docs/amb.migrate-link-formats, so future PRs will not have the tests run against them. This is a temporary workflow.

Reviewing

With the two new workflows in place, this PR should only need a spot-check.

Testing

• The latest run of the "Legacy Link Format Checker" workflow for this branch should pass (check here)
• The latest run of the "Test Link Rewrites" workflow for this branch should pass (check here)

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• To see the specific tasks where the Asana app for GitHub is being used, see below:
  • https://app.asana.com/0/0/1203453044319615