chore(ci): setup ci for server

.github/workflows/server.yml

@@ -0,0 +1,27 @@
+name: ci-server
+
+on:
+  push:
+    paths:
+      - 'server/**'
+
+defaults:
+  run:
+    working-directory: server
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Use Node.js
+        uses: actions/setup-node@v2
+        with:
+          node-version: '14.x'
+          cache: 'yarn'
+          cache-dependency-path: server/yarn.lock
+      - name: Install dependencies
+        run: yarn
+      - name: Lint
+        run: yarn lint
+