chore(deps): update coverage requirement from ~=7.6.4 to ~=7.6.7 in /api

Updates the requirements on [coverage](https://github.com/nedbat/coveragepy) to permit the latest version.
- [Release notes](https://github.com/nedbat/coveragepy/releases)
- [Changelog](https://github.com/nedbat/coveragepy/blob/master/CHANGES.rst)
- [Commits](nedbat/coveragepy@7.6.4...7.6.7)

---
updated-dependencies:
- dependency-name: coverage
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

api/requirements.txt

@@ -1,6 +1,6 @@
 captcha~=0.6.0
 celery~=5.4.0
-coverage~=7.6.4
+coverage~=7.6.7
 cryptography~=43.0.3
 Django~=5.1.2
 django-cors-headers~=4.6.0