chore: add linting workflow

.github/workflows/linter.yaml

@@ -0,0 +1,16 @@
+name: Linter
+
+on: [push, pull_request]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Install dependencies
+      run: pnpm install
+
+    - name: Lint
+      run: pnpm lint