Bump drf-yasg[validation] from 1.21.7 to 1.21.8 (#1288)

Bumps [drf-yasg[validation]](https://github.com/axnsan12/drf-yasg) from 1.21.7 to 1.21.8.
- [Release notes](https://github.com/axnsan12/drf-yasg/releases)
- [Changelog](https://github.com/axnsan12/drf-yasg/blob/master/docs/changelog.rst)
- [Commits](axnsan12/drf-yasg@1.21.7...1.21.8)

---
updated-dependencies:
- dependency-name: drf-yasg[validation]
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements.txt

@@ -5,7 +5,7 @@ django-storages==1.14.4
 django-stubs-ext==5.1.1
 djangorestframework==3.15.2
 djangorestframework-camel-case==1.4.2
-drf-yasg[validation]==1.21.7
+drf-yasg[validation]==1.21.8
 eth-typing==4.1.0
 eth-utils==4.1.1
 gunicorn==23.0.0