Bump gidgethub from 5.3.0 to 5.4.0 in /.github/workflows/requirements (llnl#149)

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
...

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

Author: dependabot[bot]

.github/workflows/requirements/unit-tests.txt

@@ -2,7 +2,7 @@ aiohttp==3.12.6
 build==1.2.2.post1
 cachetools==6.0.0
 coverage==7.8.2
-gidgethub==5.3.0
+gidgethub==5.4.0
 gidgetlab==2.1.0
 hatchling==1.27.0
 pytest-asyncio==0.24.0