[TYP] Add possible type hint to colors argument in LinearSegmentedColormap.from_list

[FelipeCybis]

• Closes [Bug]: LinearSegmentedColormap.from_list does not have all type hints for argument colors #28067

PR summary

Add possible type of colors when creating LinearSegmentedColormap.from_list(). Today only ArrayLike is used but it can also be a list or a tuple of 2-element tuples containing (value, color-like), as stated in the docs "If only colors are given, they are equidistantly mapped from the range [0, 1]; i.e. 0 maps to colors[0] and 1 maps to colors[-1]. If (value, color) pairs are given, the mapping is from value to color. This can be used to divide the range unevenly."

This can be typed as Sequence[tuple[float, ColorType]]

PR checklist

• "closes #0000" is in the body of the PR description to link the related issue
• [N/A] new and changed code is tested
• [N/A] Plotting related features are demonstrated in an example
• [N/A] New Features and API Changes are noted with a directive and release note
• Documentation complies with general and docstring guidelines

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[timhoffm]

Do we backport to 3.9?