fix(auth): detect nil interface vs nil interface

[fredbi]

• fixes When principal is concrete type auth hook can't return nil,nil to get 401 #147

Change type

Please select: 🆕 New feature or enhancement|🔧 Bug fix'|📃 Documentation update

Short description

Fixes

Full description

Checklist

• I have signed all my commits with my name and email (see DCO. This does not require a PGP-signed commit
• I have rebased and squashed my work, so only one commit remains
• I have added tests to cover my changes.
• I have properly enriched go doc comments in code.
• I have properly documented any breaking change.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.69%. Comparing base (8b594b4) to head (a6f9d23).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #425   +/-   ##
=======================================
  Coverage   81.69%   81.69%           
=======================================
  Files          50       50           
  Lines        3381     3381           
=======================================
  Hits         2762     2762           
  Misses        507      507           
  Partials      112      112           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.