🐳 Fix CI process

.github/workflows/build-backend.yaml

@@ -0,0 +1,36 @@
+name: Test build backend
+
+on:
+  pull_request:
+    paths:
+      - "backend/**"
+
+  push:
+    branches:
+      - master
+    paths:
+      - "backend/**"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [14.x]
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Install dependencies
+        working-directory: backend
+        run: npm install
+
+      - run: npm run build
+        working-directory: backend