chore(deps): update actions/upload-artifact action to v6

Author: renovate[bot]

.github/workflows/shellcheck.yml

@@ -35,7 +35,7 @@ jobs:
 
     - if: always()
       name: Upload artifact with ShellCheck defects in SARIF format
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       with:
         name: Differential ShellCheck SARIF
         path: ${{ steps.ShellCheck.outputs.sarif }}