test: define MIRAKC_ARIB_ENABLE_TESTING in test builds

[masnagam]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.09%. Comparing base (9717168) to head (435df21).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #170   +/-   ##
=======================================
  Coverage   75.09%   75.09%           
=======================================
  Files          38       38           
  Lines        4689     4689           
  Branches      477      477           
=======================================
  Hits         3521     3521           
  Misses        874      874           
  Partials      294      294           

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