accesing /pulp/api/v3/ requires auth since 3.16, while didn't before

[evgeni]

Version
3.16.3

Describe the bug
since 3.16 accessing /pulp/api/v3/ requires auth, while before that it did not.

I think this is a side effect of #1593, just not sure if that was intentional or not.

To Reproduce
Steps to reproduce the behavior:

• setup a 3.16.3 isntall
• curl -k https://localhost/pulp/api/v3/

Expected behavior
Until 3.15, this would return 200, now it returns 403, unless I do provide auth.
Accessing /pulp/api/v3/status/ still works fine without auth.

Additional context
Originally found while working on Puppet integration of 3.16+ in theforeman/puppet-pulpcore#249