docs: Clarify that enterpriseBaseURL requires /api/v3 suffix

[lindhe]

Relates to argoproj/notifications-engine#205

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 49.55%. Comparing base (6ede1a8) to head (72c640e).
Report is 1062 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #16347   +/-   ##
=======================================
  Coverage   49.55%   49.55%           
=======================================
  Files         269      269           
  Lines       47039    47039           
=======================================
  Hits        23310    23310           
  Misses      21443    21443           
  Partials     2286     2286           

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[pasha-codefresh]

@lindhe you need to do these changes in notification-engine
https://github.com/argoproj/notifications-engine/blob/master/docs/services/github.md

And after just update notification-engine version inside argocd and run make codegen

[lindhe]

Ah, I see. Thanks for the pointer!

I've created argoproj/notifications-engine#292 now, how do I proceed with the codegen? I assume the new PR must be merged first and then we update this PR with the codegen changes? Or what's the exact order of operations?