Install Node.js and mystmd for GHA

Author: troyraen

.github/workflows/ci_publish.yml

@@ -27,6 +27,14 @@ jobs:
     steps:
       - uses: actions/checkout@v5
 
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+
+      - name: Install mystmd
+        run: npm install mystmd
+
       - name: Setup Python
         uses: actions/setup-python@v6
         with:
@@ -62,4 +70,4 @@ jobs:
           git rm --cached -r .
           git add --pathspec-from-file=deployed_notebooks_manifest.in --force
           git commit -m "Deploy notebooks for commit ${gith}"
-          git push origin deployed_notebooks --force
+          git push origin deployed_notebooks --force

.github/workflows/ci_tests_run_notebooks.yml

@@ -65,6 +65,14 @@ jobs:
     steps:
       - uses: actions/checkout@v5
 
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '22'
+
+      - name: Install mystmd
+        run: npm install mystmd
+
       - name: Setup Python
         uses: actions/setup-python@v6
         with: