Bump nosborn/github-action-markdown-cli from 1.1.1 to 2 (#50)

Bumps [nosborn/github-action-markdown-cli](https://github.com/nosborn/github-action-markdown-cli) from 1.1.1 to 2.
- [Release notes](https://github.com/nosborn/github-action-markdown-cli/releases)
- [Commits](nosborn/github-action-markdown-cli@v1.1.1...v2)

---
updated-dependencies:
- dependency-name: nosborn/github-action-markdown-cli
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/markdownlint.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@master
-    - uses: nosborn/github-action-markdown-cli@v1.1.1
+    - uses: nosborn/github-action-markdown-cli@v2
       name: Markdownlint
       with:
         files: .