refactor: move configtest into core

[alexander-akait]

Summary

refactor merge configtest into core

What kind of change does this PR introduce?

refactor

Did you add tests for your changes?

Existing

Does this PR introduce a breaking change?

No

If relevant, what needs to be documented once your changes are merged or what have you already documented?

Nothing

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.65%. Comparing base (ab0545e) to head (d98b651).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4654   +/-   ##
=======================================
  Coverage   95.65%   95.65%           
=======================================
  Files           2        2           
  Lines          23       23           
  Branches        4        4           
=======================================
  Hits           22       22           
  Misses          1        1           

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