Simplify GitHub Actions workflow

Removed installation and build steps from workflow.

Author: NssGourav

.github/workflows/learn-github-actions.yml

@@ -18,11 +18,5 @@ jobs:
         with:
           node-version: 20
 
-      - name: Install dependencies
-        run: npm install
-
       - name: Run tests
         run: npm test
-
-      - name: Build project
-        run: npm run build