Remove defaults from class constructors and validators

[jamesmbaazam]

This PR closes #161 by removing the empty defaults that were passed to the constructor and validation functions of <epichains_tree> and <epichains_summary> objects.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (d499296) 99.11% compared to head (de9301b) 99.11%.
Report is 2 commits behind head on main.

❗ Current head de9301b differs from pull request most recent head 6761962. Consider uploading reports for the commit 6761962 to get more accurate results

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #172   +/-   ##
=======================================
  Coverage   99.11%   99.11%           
=======================================
  Files           8        8           
  Lines         562      562           
=======================================
  Hits          557      557           
  Misses          5        5           

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