build(deps): bump watchdog from 7.0.0 to 7.1.0 in /tools/serve_header

Bumps [watchdog](https://github.com/gorakhargosh/watchdog) from 7.0.0 to 7.1.0.
- [Release notes](https://github.com/gorakhargosh/watchdog/releases)
- [Changelog](https://github.com/gorakhargosh/watchdog/blob/master/changelog.rst)
- [Commits](https://github.com/gorakhargosh/watchdog/compare/v7.0.0...v7.1.0)

---
updated-dependencies:
- dependency-name: watchdog
  dependency-version: 7.1.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

tools/serve_header/requirements.txt

@@ -1,2 +1,2 @@
 PyYAML==6.0.3
-watchdog==7.0.0
+watchdog==7.1.0