Fix: Run adapt install in GitHub Pages workflow (fix #3737) (#3738)

Author: swashbuck

.github/workflows/build-and-deploy.yml

@@ -19,7 +19,9 @@ jobs:
           node-version: "lts/*"
 
       - name: Install dependencies
-        run: npm ci
+        run: |
+          npm ci
+          npx -y -p adapt-cli adapt install
 
       - name: Build course
         run: grunt build