v3 - Column - Allow Enum in ReturnType for Column getContent/renderContent

[lrljoe]

This fix is to allow casted columns via Enum.

Tests for this will follow in future versions.

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[codecov]

Codecov Report

Merging #1436 (929e56a) into v3-develop (cb2d9c9) will not change coverage.
Report is 3 commits behind head on v3-develop.
The diff coverage is 100.00%.

@@              Coverage Diff              @@
##             v3-develop    #1436   +/-   ##
=============================================
  Coverage         88.00%   88.00%           
  Complexity         1210     1210           
=============================================
  Files                85       85           
  Lines              2950     2950           
=============================================
  Hits               2596     2596           
  Misses              354      354           

Files	Coverage Δ
src/Views/Traits/Helpers/ColumnHelpers.php	90.86% <100.00%> (ø)