Adds simple checks on PR

.github/actions/setup/action.yml

@@ -5,13 +5,13 @@ runs:
   using: composite
   steps:
     - name: Setup Node.js
-      uses: actions/setup-node@v3
+      uses: actions/setup-node@64ed1c7eab4cce3362f8c340dee64e5eaeef8f7c # v3.6.0
       with:
         node-version-file: .nvmrc
 
     - name: Cache dependencies
       id: yarn-cache
-      uses: actions/cache@v3
+      uses: actions/cache@88522ab9f39a2ea568f7027eddc7d8d8bc9d59c8 # v3.3.1
       with:
         path: |
           **/node_modules

.github/workflows/checks.yml

@@ -0,0 +1,18 @@
+name: Checks
+on:
+  - pull_request
+jobs:
+  checks:
+    runs-on: ubuntu-latest
+    concurrency:
+      group: ${{ github.workflow }}-pr-staticcheck-${{ github.head_ref || github.run_id }}
+      cancel-in-progress: true
+    steps:
+      - id: checkout
+        uses: actions/checkout@8e5e7e5ab8b370d6c329ec480221332ada57f0ab # v3.5.2
+      - id: setup
+        uses: ./.github/actions/setup
+      - id: tsc
+        run: yarn typecheck
+      - id: lint
+        run: yarn lint