ci(gh-actions): create CI action for testing and linting

Author: omBratteng

.github/workflows/ci.yml

@@ -0,0 +1,50 @@
+name: Continuous Integration
+
+on:
+  push:
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: ['10', '12', '14']
+    name: "[v${{ matrix.node-version }}] lint and test"
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v2-beta
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      # Check if cache exists, based on the hash of the lockfile
+      - name: Cache node_modules
+        id: cache-node_modules
+        uses: actions/cache@v2
+        with:
+          path: node_modules
+          key: ${{ runner.os }}-node-${{matrix.node-version}}-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-${{matrix.node-version}}-
+            ${{ runner.os }}-node-
+            ${{ runner.os }}-
+
+      # If there is no cache available, we run npm installation in CI mode
+      - name: Install dependencies
+        if: steps.cache-node_modules.outputs.cache-hit != 'true'
+        run: npm ci
+
+      - name: Lint
+        run: npm run lint
+
+      - name: Run tests
+        run: npm run test
+
+      # Build and check if it builds ok.
+      - name: Build
+        env:
+          BUNDLESIZE_GITHUB_TOKEN: ${{ secrets.BUNDLESIZE }}
+        run: npm run build