CI: explicitly add dependency on findutils

I've seen a "xargs: command not found" from GitHub. Evidently findutils
isn't provided by default even though it is "Essential: yes", so specify
it explicitly.

I sorted the dependency order here now because there are more than two.

Author: basak-qcom

.github/workflows/static-checks.yml

@@ -51,7 +51,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Install ShellCheck
-        run: sudo apt update && sudo apt -y install shellcheck file
+        run: sudo apt update && sudo apt -y install file findutils shellcheck
 
       - uses: actions/checkout@v4
         with: