IIS parser: Support few more username variations

[pyllyukko]

E.g.:

• realm/username
• username@realm

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.98%. Comparing base (8ee35bb) to head (43a876e).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4904   +/-   ##
=======================================
  Coverage   84.98%   84.98%           
=======================================
  Files         431      431           
  Lines       38505    38505           
=======================================
  Hits        32725    32725           
  Misses       5780     5780           

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

[joachimmetz]

@pyllyukko thanks for the changes could you add corresponding test cases for these as well?

[pyllyukko]

@pyllyukko thanks for the changes could you add corresponding test cases for these as well?

Will do.

[joachimmetz]

LGTM, thanks for the changes