Update the checkout action version (#32)

Author: bharatr21

.github/steps/2-add-a-job.md

@@ -27,7 +27,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Output the input value
         run: |