build(deps): bump drf-spectacular from 0.27.2 to 0.28.0

Bumps [drf-spectacular](https://github.com/tfranzel/drf-spectacular) from 0.27.2 to 0.28.0.
- [Release notes](https://github.com/tfranzel/drf-spectacular/releases)
- [Changelog](https://github.com/tfranzel/drf-spectacular/blob/master/CHANGELOG.rst)
- [Commits](tfranzel/drf-spectacular@0.27.2...0.28.0)

---
updated-dependencies:
- dependency-name: drf-spectacular
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

requirements.txt

@@ -79,7 +79,7 @@ djangorestframework-gis==1.0
 djangorestframework-guardian==0.3.0
 drf-extensions==0.7.1
 drf-writable-nested==0.7.0
-drf-spectacular==0.27.2
+drf-spectacular==0.28.0
 dynamic-rest==2.3.0
 Markdown==3.6