Add es-check to verify builds produce valid es5 code

.github/workflows/lint.yml

@@ -7,6 +7,32 @@ on:
     branches: [ master, release* ]
 
 jobs:
+  run-escheck:
+    name: Run es-check
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out Git repository
+        uses: actions/checkout@2541b1294d2704b0964813337f33b291d3f8596b # tag=v3
+
+      - name: Setup node environment
+        uses: actions/setup-node@969bd2663942d722d85b6a8626225850c2f7be4b # tag=v3.5.0
+        with:
+          node-version: 16
+          check-latest: true
+          cache: npm
+
+      - name: Install Node.js dependencies
+        run: npm ci --no-audit
+        env:
+          SKIP_PREPARE: true
+
+      - name: Run a production build
+        run: npm run build:production
+
+      - name: Run es-check
+        run: npm run escheck
+
   run-eslint:
     name: Run eslint
     runs-on: ubuntu-latest