Skip to validate username when update user profile

[stonezdj]

fixes #19528

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Comprehensive Summary of your change

Issue being fixed

Fixes #(issue)

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• Well Written Title and Summary of the PR
• Label the PR as needed. "release-note/ignore-for-release, release-note/new-feature, release-note/update, release-note/enhancement, release-note/community, release-note/breaking-change, release-note/docs, release-note/infra, release-note/deprecation"
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• Made sure tests are passing and test coverage is added if needed.
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[codecov]

Codecov Report

Merging #19552 (5a6b598) into main (35a605e) will increase coverage by 0.00%.
The diff coverage is 80.00%.

@@           Coverage Diff           @@
##             main   #19552   +/-   ##
=======================================
  Coverage   67.51%   67.51%           
=======================================
  Files         988      988           
  Lines      108777   108780    +3     
  Branches     2737     2737           
=======================================
+ Hits        73437    73448   +11     
+ Misses      31374    31371    -3     
+ Partials     3966     3961    -5     

Flag	Coverage Δ
unittests	67.51% <80.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/server/v2.0/handler/user.go	19.55% <80.00%> (-0.90%)	⬇️

... and 7 files with indirect coverage changes

[chlins]

lgtm