test(chart): use css variables in place of className #5282

Job	Run time
Status check > Unit	1s
CI \| Unit	1s
CI \| Visual	1s
Compile themes / run	46s
Lint scripts / run	49s
Render test pages / verify	7s
Lint styles / run (default)	1m 6s
Lint styles / run (bootstrap)	1m 6s
Lint styles / run (material)	1m 6s
Lint styles / run (classic)	1m 13s
Lint styles / run (fluent)	1m 10s
Render test pages / run	2m 26s
Status check > Lint scripts	1s
Status check > Lint styles	1s
Status check > A11y / prepare	1s
Create screenshots / run (default)	2m 17s
Create screenshots / run (bootstrap)	2m 19s
Create screenshots / run (material)	2m 26s
Create screenshots / run (classic)	2m 0s
Create screenshots / run (fluent)	3m 1s
Status check > A11y / run-checks (1)	2m 18s
Status check > A11y / run-checks (2)	2m 28s
Status check > A11y / run-checks (3)	2m 31s
Status check > A11y / run-checks (4)	2m 41s
Detect changes	13s
Status check > Visual	1s
	32m 10s

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