Updated Colourful from 2.0.5 to 3.0.0 (only benchmarks affected)

[tompazourek]

Prerequisites

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Description

The Colourful library is used in the benchmarks, and recently, there was a version 3.0.0 released. I updated the package reference, and the converter code to reflect the new API.

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #1691 (7a342a1) into master (fe65a38) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1691   +/-   ##
=======================================
  Coverage   84.33%   84.33%           
=======================================
  Files         816      816           
  Lines       35908    35908           
  Branches     4173     4173           
=======================================
  Hits        30282    30282           
  Misses       4804     4804           
  Partials      822      822           

Flag	Coverage Δ
unittests	84.33% <ø> (ø)

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[JimBobSquarePants]

Ah fantastic @tompazourek thanks for this!

Did you run the benchmarks? Any changes?

[tompazourek]

@JimBobSquarePants I ran the benchmarks locally and noticed that Colourful performed a bit better than before. I think in one case (I think it was the Lab conversion), it might even have outperformed the current ImageSharp solution.

[JimBobSquarePants]

@tompazourek Nice work!