Remove StatsPlots warnings

[BioTurboNick]

Implementation of #2001 . Will move shorthands to StatsPlots.jl

Fix #3746

[codecov]

Codecov Report

Merging #3357 (c918943) into master (f76390c) will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3357      +/-   ##
==========================================
- Coverage   64.81%   64.77%   -0.04%     
==========================================
  Files          26       26              
  Lines        6539     6532       -7     
==========================================
- Hits         4238     4231       -7     
  Misses       2301     2301              

Impacted Files	Coverage Δ
src/args.jl	75.70% <ø> (+<0.01%)	⬆️
src/shorthands.jl	45.83% <ø> (ø)
src/backends/hdf5.jl	82.73% <0.00%> (-0.14%)	⬇️
src/backends/gr.jl	87.50% <0.00%> (-0.10%)	⬇️
src/recipes.jl	57.24% <0.00%> (-0.06%)	⬇️

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