docs(vgdp-micro-service.md): correct typo in VGDP acronym description to match Unified Repository design reference

[kaovilai]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.15%. Comparing base (60e9277) to head (9855cd2).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #8239      +/-   ##
==========================================
+ Coverage   59.13%   59.15%   +0.01%     
==========================================
  Files         367      367              
  Lines       30777    30777              
==========================================
+ Hits        18200    18206       +6     
+ Misses      11118    11113       -5     
+ Partials     1459     1458       -1     

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[kaovilai]

/kind changelog-not-required