v3 DateRange - Icon Styling, FilterHelper Method

[lrljoe]

Fixes unstyled DateRange Calendar Icon for Bootstrap Adds new FilterHelper method for generating wire:key for Filters Adds new tests for FilterCustomPosition

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[codecov[bot]]

Codecov Report

Merging #1490 (45ae2ab) into v3-develop (5a2c14e) will increase coverage by 0.04%. The diff coverage is 100.00%.

@@               Coverage Diff                @@
##             v3-develop    #1490      +/-   ##
================================================
+ Coverage         88.03%   88.08%   +0.04%     
- Complexity         1239     1251      +12     
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  Files                88       88              
  Lines              3001     3013      +12     
================================================
+ Hits               2642     2654      +12     
  Misses              359      359              

Files	Coverage Δ
src/Views/Filters/DateRangeFilter.php	87.27% <100.00%> (+1.27%)	:arrow_up:
src/Views/Traits/Helpers/FilterHelpers.php	97.33% <100.00%> (+0.07%)	:arrow_up: