Add CI with some unit test and lint

Author: Kudo

.github/workflows/build.yml

@@ -0,0 +1,50 @@
+name: Build
+
+on:
+  push:
+    path-ignore:
+      - '**/*.md'
+  pull_request:
+    branches:
+      - master
+    path-ignore:
+      - '**/*.md'
+
+jobs:
+  build-and-test:
+    name: Build and Test
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node: [10, 12]
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node }}
+
+      - name: Get yarn cache directory path
+        id: yarn-cache-dir-path
+        run: echo "::set-output name=dir::$(yarn cache dir)"
+
+      - uses: actions/cache@v1
+        id: yarn-cache # use this to check for `cache-hit` (`steps.yarn-cache.outputs.cache-hit != 'true'`)
+        with:
+          path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
+          key: ${{ runner.os }}-node${{ matrix.node }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-node${{ matrix.node}}-yarn-
+
+      - name: Install dependencies
+        run: yarn --frozen-lockfile
+
+      - name: Run unit tests
+        run: yarn test:ci:unit
+
+      - name: Lint
+        run: yarn lint
+
+      - name: Build
+        run: yarn build