feat(subscription): filter to short-circuit form processing

[miguelpeixe]

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Changes proposed in this Pull Request:

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 23.28%. Comparing base (013d38d) to head (b7fff8d).

Additional details and impacted files

@@            Coverage Diff            @@
##              trunk    #1736   +/-   ##
=========================================
  Coverage     23.28%   23.28%           
  Complexity     2709     2709           
=========================================
  Files            49       49           
  Lines         10753    10753           
=========================================
  Hits           2504     2504           
  Misses         8249     8249           

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