Address code scanning warnings

Author: dstebila

.github/workflows/markdownlint.yml

@@ -1,5 +1,8 @@
 name: Markdown Lint
 
+permissions:
+  contents: read
+
 on:
   pull_request:
     paths:
@@ -11,15 +14,20 @@ jobs:
 
     steps:
       - name: Checkout repo
-        uses: actions/checkout@v4
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # pin@v4
 
       - name: Set up Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # pin@v4
         with:
           node-version: '18'
 
       - name: Install markdownlint-cli
-        run: npm install -g markdownlint-cli
+        run: |
+          cp .github/workflows/package.json . && \
+          cp .github/workflows/package-lock.json . && \
+          npm install -g && \
+          rm package.json && \
+          rm package-lock.json && \
 
       - name: Run markdownlint
         run: markdownlint '**/*.md' --ignore node_modules