Add Remove to remove an item from a slice

[MarkRosemaker]

This PR adds a function to remove an element from a slice.

h/t to https://yourbasic.org/golang/delete-element-slice/

[codecov-commenter]

Codecov Report

Merging #180 (95bf3bc) into master (c9f230d) will increase coverage by 0.07%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #180      +/-   ##
==========================================
+ Coverage   90.36%   90.43%   +0.07%     
==========================================
  Files          13       13              
  Lines        1495     1506      +11     
==========================================
+ Hits         1351     1362      +11     
  Misses        141      141              
  Partials        3        3              

Flag	Coverage Δ
unittests	90.43% <100.00%> (+0.07%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
slice.go	98.19% <100.00%> (+0.07%)	⬆️

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[samber]

Hi @MarkRosemaker and thanks for your first contribution.

Could you please return a new slice instead of modifying the collection?