Display SAML login icon for /api/login page

Please confirm the following

• I agree to follow this project's code of conduct.
• I have checked the current issues for duplicates.
• I understand that AWX is open source software provided for free and that I might not receive a timely response.

Feature type

Enhancement to Existing Feature

Feature Summary

When requesting an authorization-code at /api/o/authorize, users can't use SAML to login.

I see 2 possible feature enhancement to correct that :

1. Display an SAML login button on that page
2. Redirect to web UI login page, then redirect to /api/o/authorize

Select the relevant components

• UI
• API
• Docs
• Collection
• CLI
• Other

Steps to reproduce

• Add an SAML provider in AWX settings.
• Make sure to logout from AWX.
• Go to /api/o/authorize route, it redirects you to /api/login/?next=/api/o/authorize/

Current results

Users are only able to login with username + password.

Sugested feature result

Users should be able to login via SAML.

Additional information

No response