feat: support overriding ext_auth path

[rudrakhp]

What type of PR is this?

feat: support overriding ext_auth path

What this PR does / why we need it:
Adds support for complete override path used for ext_auth instead of prefix behavior today.

Which issue(s) this PR fixes:

Fixes #7992

Release Notes: Yes

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 74.34%. Comparing base (fae7f19) to head (ca3a485).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #8612   +/-   ##
=======================================
  Coverage   74.33%   74.34%           
=======================================
  Files         243      243           
  Lines       38147    38152    +5     
=======================================
+ Hits        28358    28365    +7     
+ Misses       7801     7800    -1     
+ Partials     1988     1987    -1     

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