Validate javascript on PRs

.github/workflows/check.yml

@@ -1,4 +1,4 @@
-name: HTML Check
+name: Check HTML/JS is valid
 
 on:
   pull_request:
@@ -9,8 +9,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - name: HTML5 Validator
+    - name: Run HTML5 Validator
       uses: Cyb3r-Jak3/html5validator-action@v7.2.0
       with:
         config: ./.github/html5validator.yml
         css: true
+    - name: Install modules for eslint
+      run: npm i
+    - name: Run ESLint
+      run: npx eslint . --ext .js,.html