add to data quality section link to label error finding with cleanlab

[jwmueller]

This same procedure has been used in many companies like Google, Amazon, Wells Fargo, etc. to find label errors in internal datasets.

It has also been featured in various media: [1, 2, 3, 4, 5, 6, 7, 8]

[eugeneyan]

Thanks for suggesting this. It seems more like a how-to and less of an industry case study. Thus, we won't be including it.