Workflow npm install on PRs (#86)

* Run npm install on PRs

* Edit step name

.github/workflows/build.yml

@@ -0,0 +1,25 @@
+name: Build 
+
+on:
+  pull_request:
+    branches: [ main ]
+    paths-ignore:
+      - '**/README.md'
+      - .gitignore
+      - LICENSE
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [18.x]
+    steps:
+    - uses: actions/checkout@v3
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v3
+      with:
+        node-version: ${{ matrix.node-version }}
+        cache: 'npm'
+    - name: Npm install
+      run: npm install