Removed export_cmake hack

[cmaglie]

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• Tests for the changes have been added (for bug fixes / features)
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• configuration.schema.json updated if new parameters are added.

What kind of change does this PR introduce?

Remove the undocumented export_cmake hack. It's buggy and unmaintained.

What is the current behavior?

What is the new behavior?

Does this PR introduce a breaking change, and is titled accordingly?

Other information

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (db53f81) 67.61% compared to head (42f7b89) 68.45%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2482      +/-   ##
==========================================
+ Coverage   67.61%   68.45%   +0.83%     
==========================================
  Files         207      206       -1     
  Lines       20765    20474     -291     
==========================================
- Hits        14041    14015      -26     
+ Misses       5582     5319     -263     
+ Partials     1142     1140       -2     

Flag	Coverage Δ
unit	68.45% <ø> (+0.83%)	⬆️

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