[Vis colors] Replace observability plotly colors with ouiPaletteColorBlind()

[joshuarrrr]

Obervability visualizations define the PLOTLY_COLOR const:

dashboards-observability/common/constants/shared.ts

Lines 85 to 97 in 4ab8089

	// Color Constants
	export const PLOTLY_COLOR = [
	'#3CA1C7',
	'#8C55A3',
	'#DB748A',
	'#F2BE4B',
	'#68CCC2',
	'#2A7866',
	'#843769',
	'#374FB8',
	'#BD6F26',
	'#4C636F',
	];

(For visual comparison, see opensearch-project/oui#601)

Instead of a hard-coded list, it should just use the default OUI colors from euiPaletteColorBlind()

For a similar mitigation, see opensearch-project/OpenSearch-Dashboards#4366