[Docs] sort-comp: add class component examples

[maurer2]

Hello, I updated the examples for sort-comp, that were still using createClass with class component examples.

Cheers

[codecov]

Codecov Report

Merging #3339 (caadfd3) into master (bdbd2a4) will not change coverage.
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  Files         123      123           
  Lines        8788     8788           
  Branches     3190     3190           
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  Hits         8587     8587           
  Misses        201      201           

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[ljharb]

Rather than replacing these examples, let's add them so we have both

[maurer2]

Okay, I restored the createClass examples and fixed the formatting issues.
Cheers

[maurer2]

Implemented the onClick changes, but I think onClick = this.onClick.bind(this); needs to be in the constructor to avoid a Property 'onClick' is used before its initialization` warning

[ljharb]

Thanks!