Color improvements to visualizations

[kzadurska]

Heatmap uses hardcoded orange color instead of brand primary color.
Scatterplot on the feature branch has hardcoded color for heatmap summary (similar to item-measure).

• Heatmap uses brand color
• Ability to set secondary brand color
• Scatterplot heatmap summary uses secondary color

[adrianmroz-allegro]

I think we should define viz colours and do not use brand css variable. Also NORMAL_COLORS.

[kzadurska]

I have an idea, we will see how you like it 🙃