chore(deps): remove unused custom event polyfill

[ghiscoding]

• no longer needed since this was introduced for IE specifically but since it is no longer needed, we can safely remove it all

[bolt-new-by-stackblitz]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.0%. Comparing base (439977b) to head (8596724).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1994   +/-   ##
=======================================
  Coverage   100.0%   100.0%           
=======================================
  Files         195      195           
  Lines       35931    35931           
  Branches    10651    10651           
=======================================
  Hits        35931    35931           

Flag	Coverage Δ
angular	100.0% <ø> (ø)
universal	100.0% <ø> (ø)

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