Contrast module now uses changePixel Method

[rishabhshuklax]

Fixes #1472

Contrast module now uses changePixel Method instead of extraManipulation which has made it faster.

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[codecov]

Codecov Report

Merging #1482 into main will decrease coverage by 0.09%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##             main    #1482     +/-   ##
=========================================
- Coverage   64.74%   64.64%   -0.1%     
=========================================
  Files         126      126             
  Lines        2590     2594      +4     
  Branches      416      416             
=========================================
  Hits         1677     1677             
- Misses        913      917      +4

Impacted Files	Coverage Δ
examples/lib/insertPreview.js	13.51% <ø> (ø)	⬆️
examples/lib/defaultHtmlStepUi.js	10.98% <0%> (-0.25%)	⬇️

[rishabhshuklax]

@publiclab/is-reviewers please review this

[harshkhandeparkar]

Awesome!

[harshkhandeparkar]

LGTM! The test pass too.

[jywarren]

Great work!!