Create lint.yml (Github Action)

.github/workflows/lint.yml

@@ -0,0 +1,39 @@
+name: Lint Code Base
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  workflow_dispatch:
+
+jobs:
+  run-lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Get yarn cache directory path
+        id: yarn-cache-dir-path
+        run: echo "::set-output name=dir::$(yarn cache dir)"
+
+      - name: Cache node_modules
+        uses: actions/cache@v2
+        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: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-yarn-
+
+      - name: Install dependencies
+        run: yarn --cwd ./frontend/ && yarn --cwd ./backend
+
+      - name: Lint Frontend
+        working-directory: ./frontend
+        run: yarn lint
+
+      - name: Lint Backend
+        working-directory: ./backend
+        run: yarn lint