Tracking issue for upgrade to latest markdownlint-cli2 across projects

Issue

The latest version of markdownlint-cli2 is preferable in most cases now. It's now what's running under the hood in the VS Code extension, is designed to work better in CI/CD pipelines, and is actively maintained by the main markdownlint author. This issue is tracking the various MRs and work done to:

• Ensure all projects standardize on a single version of markdownlint-cli2 (not markdownlint-cli "1")
• Make changes across projects to support the various rule changes in the newer versions of markdownlint, including:
  • MD024/no-duplicate-heading
  • MD044/proper-names
  • MD045/no-alt-text
  • MD055/table-pipe-style
  • MD056/table-column-count