Bump captcha from 0.5.0 to 0.6.0 (#353)

Bumps [captcha](https://github.com/lepture/captcha) from 0.5.0 to 0.6.0.
- [Release notes](https://github.com/lepture/captcha/releases)
- [Changelog](https://github.com/lepture/captcha/blob/master/docs/changelog.rst)
- [Commits](https://github.com/lepture/captcha/compare/v0.5.0...v0.6.0)

---
updated-dependencies:
- dependency-name: captcha
  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>

requirements.txt

@@ -6,7 +6,7 @@ redis==5.2.0
 apscheduler==3.10.4
 pymongo==4.10.1
 tornado==6.4.2
-captcha==0.5.0
+captcha==0.6.0
 passlib==1.7.4
 fakeredis==2.21.1
 filetype==1.2.0