Bump django-auth-ldap from 4.5.0 to 4.6.0 in /requirements

Bumps [django-auth-ldap](https://github.com/django-auth-ldap/django-auth-ldap) from 4.5.0 to 4.6.0.
- [Release notes](https://github.com/django-auth-ldap/django-auth-ldap/releases)
- [Changelog](https://github.com/django-auth-ldap/django-auth-ldap/blob/master/docs/changes.rst)
- [Commits](django-auth-ldap/django-auth-ldap@4.5.0...4.6.0)

---
updated-dependencies:
- dependency-name: django-auth-ldap
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements/ldap.txt

@@ -1,2 +1,2 @@
-django-auth-ldap==4.5.0
+django-auth-ldap==4.6.0
 python-ldap==3.4.3