[chore][cmd/mdatagen] fix #12298 unit tests failures

[cuichenli]

Description

The current implementation is not working in the sample projects. I reviewed the PR that introduced these changes and found no explanation for them. I believe it’s reasonable to revert these changes, so I’ve created this PR.

Please let me know if I’ve missed anything. Thank you!

Link to tracking issue

Fixes #12298

Testing

$ cd cmd/mdatagen 
$ go install .
$ make generate 
$ git status  # run this to check there is no change in the generated files 
$ make test

Documentation

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.19%. Comparing base (2e344f7) to head (b09e8fd).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #12474   +/-   ##
=======================================
  Coverage   92.19%   92.19%           
=======================================
  Files         465      465           
  Lines       25194    25194           
=======================================
  Hits        23228    23228           
  Misses       1570     1570           
  Partials      396      396           

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[cuichenli]

i will create one new account and try it again 🤯

[gudecatch]

#12477