fix: LEAP-2058: delete unused upload-example endpoint

[jombooth]

I verified that this endpoint is completely unused; let's go ahead and remove it.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.13%. Comparing base (ec3c97f) to head (b4f2af9).
Report is 4 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #7440      +/-   ##
===========================================
- Coverage    78.53%   78.13%   -0.40%     
===========================================
  Files          195      195              
  Lines        15767    15735      -32     
===========================================
- Hits         12382    12294      -88     
- Misses        3385     3441      +56     

Flag	Coverage Δ
pytests	78.13% <ø> (-0.40%)	⬇️

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