fix: Add the /key path to API gateaway

[lindseysimple]

Relates to #5038. Add the POST /key path to API gateaway from security-proxy-auth.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[cloudxxx8]

LGTM

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 28.11%. Comparing base (02e35b0) to head (2a92b0a).

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Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5047   +/-   ##
=======================================
  Coverage   28.11%   28.11%           
=======================================
  Files         256      256           
  Lines       18462    18462           
=======================================
  Hits         5191     5191           
  Misses      12071    12071           
  Partials     1200     1200           

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