Update Macbeth Dictionary

[wpwupingwp]

In Macbeth colorchecker dictionary, the RGB value of 21.neutral 6.5(.44*) and 23.neutral 3.5(.1.05*) seems to be wrong, while Lab values are correct.

Citation: https://babelcolor.com/index_htm_files/RGB%20Coordinates%20of%20the%20Macbeth%20ColorChecker.pdf

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