Bump DavidAnson/markdownlint-cli2-action from 14.0.0 to 15.0.0 (#2653)

Author: dependabot[bot]

.github/workflows/lint.yml

@@ -31,4 +31,4 @@ jobs:
     steps:
       - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
       - name: Lint markdown
-        uses: DavidAnson/markdownlint-cli2-action@455b6612a7b7a80f28be9e019b70abdd11696e4e
+        uses: DavidAnson/markdownlint-cli2-action@510b996878fc0d1a46c8a04ec86b06dbfba09de7