build(deps): bump gidgethub from 5.3.0 to 5.4.0 (#233)

Bumps [gidgethub](https://github.com/brettcannon/gidgethub) from 5.3.0 to 5.4.0.
- [Release notes](https://github.com/brettcannon/gidgethub/releases)
- [Changelog](https://github.com/gidgethub/gidgethub/blob/main/docs/changelog.rst)
- [Commits](gidgethub/gidgethub@v5.3.0...v5.4.0)

---
updated-dependencies:
- dependency-name: gidgethub
  dependency-version: 5.4.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

pyproject.toml

@@ -8,7 +8,7 @@ dependencies = [
   "aiohttp==3.14.3",
   "cachetools==7.1.8",
   "fixit==2.2.1",
-  "gidgethub==5.3.0",
+  "gidgethub==5.4.0",
   "libcst==1.1.0",
   "sentry-sdk==2.68.1",
 ]