Heatmap hover color unchangeable

[vaadin-bot]

Originally by niko.hellgren

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Setting a hover color (or any other stylings) to the States object of PlotOptionsHeatmap does nothing. To reproduce:

1. Take the example code from https://demo.vaadin.com/charts/#HeatMapExample
2. Add the following definitions to the plotOptionsHeatmap object

Hover hover = new Hover();
hover.setFillColor(SolidColor.CRIMSON); // Or any other Color
States states = new States();
states.setHover(hover);     
plotOptionsHeatmap.setStates(states);

3. Color of the cell upon mouseover is still the default Maya Blue

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Imported from https://dev.vaadin.com/ issue #19763