GitHub: Changes the bash/sh linting workflow to allow it to be requir…

…ed. (awsdocs#6158)

.github/workflows/sh-check.yml

@@ -3,15 +3,20 @@
 name: Lint Bash
 
 on:
-  pull_request: # This action does not use the paths option.
+  pull_request:
   workflow_dispatch:
 
 jobs:
   sh-checker:
     name: Lint Bash
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - name: Checkout files
+        uses: actions/checkout@v4
+        with:
+          sparse-checkout: |
+            .github
+            aws-cli
       - name: Lint Bash
         uses: luizm/action-sh-checker@master
         env: