Add markdown lint action

Author: dflook

.github/workflows/test.yaml

@@ -97,20 +97,16 @@ jobs:
           ./actionlint
           ./actionlint example_workflows/*.yaml
 
-      - name: Lint READMEs
-        uses: DavidAnson/markdownlint-cli2-action@v19
-        with:
-          config: '.config/.markdownlint.jsonc'
-          globs: '**/README.md'
-
       - name: Lint CHANGELOG
         uses: DavidAnson/markdownlint-cli2-action@v19
         with:
-          config: '.config/.markdownlint.jsonc'
+          config: '.config/.markdownlint.yaml'
           globs: 'CHANGELOG.md'
 
       - name: Lint Other Markdown
         uses: DavidAnson/markdownlint-cli2-action@v19
         with:
-          config: '.config/.markdownlint.jsonc'
-          globs: 'docs/*.md'
+          config: '.config/.markdownlint.yaml'
+          globs: |
+            docs/*.md
+            **/README.md