Add building test

It was not tested before. If it works, the deploy works (hopefully).

Author: Hans5958

.github/workflows/lint.yml

@@ -36,3 +36,29 @@ jobs:
       - name: Run Prettier
         if: ${{ !cancelled() }}
         run: npx prettier --check .
+  test:
+    name: Test building
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+      - name: Setup Node.js
+        uses: actions/setup-node@v6
+        with:
+          node-version: 18
+      - name: Get npm cache directory
+        id: npm-cache-dir
+        shell: bash
+        run: echo "dir=$(npm config get cache)" >> ${GITHUB_OUTPUT}
+      - name: Cache dependencies
+        uses: actions/cache@v5
+        with:
+          path: ${{ steps.npm-cache-dir.outputs.dir }}
+          key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-
+      - name: Install dependencies
+        run: npm ci
+      - name: Test building
+        if: ${{ !cancelled() }}
+        run: npm run build