build: fix change detection

---
type: pre_commit_static_analysis_report
description: Results of running static analysis checks when committing changes.
report:
  - task: lint_filenames
    status: passed
  - task: lint_editorconfig
    status: passed
  - task: lint_markdown
    status: na
  - task: lint_package_json
    status: na
  - task: lint_repl_help
    status: na
  - task: lint_javascript_src
    status: na
  - task: lint_javascript_cli
    status: na
  - task: lint_javascript_examples
    status: na
  - task: lint_javascript_tests
    status: na
  - task: lint_javascript_benchmarks
    status: na
  - task: lint_python
    status: na
  - task: lint_r
    status: na
  - task: lint_c_src
    status: na
  - task: lint_c_examples
    status: na
  - task: lint_c_benchmarks
    status: na
  - task: lint_c_tests_fixtures
    status: na
  - task: lint_shell
    status: na
  - task: lint_typescript_declarations
    status: na
  - task: lint_typescript_tests
    status: na
  - task: lint_license_headers
    status: passed
---

Author: Planeshifter

.github/workflows/update_contributors.yml

@@ -78,10 +78,15 @@ jobs:
         run: |
           make update-contributors
 
-          if [[ -z "$(git status --porcelain)" ]]; then
+          # Stage *all* tracked and untracked changes first…
+          git add -A
+
+          # If the index is identical to HEAD, nothing real changed:
+          if git diff --cached --quiet; then
             echo "No changes to commit."
             echo "changed=false" >> $GITHUB_OUTPUT
           else
+            echo "Changes detected."
             echo "changed=true" >> $GITHUB_OUTPUT
           fi
 
@@ -129,6 +134,7 @@ jobs:
 
       # Create a pull request summary:
       - name: 'Create summary'
+        if: steps.update-contributors.outputs.changed == 'true'
         run: |
           echo "# :tada: Pull Request created! :tada:" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY