chore(html): add gantt spec #3312

Job	Run time
Status check > Unit	1s
CI \| Unit	1s
CI \| Visual	1s
Lint scripts / run	58s
Lint styles / run (default)	2m 11s
Compile themes / run	37s
Render test pages / verify	9s
Lint styles / run (bootstrap)	2m 50s
Lint styles / run (material)	2m 14s
Lint styles / run (classic)	2m 11s
Lint styles / run (nouvelle)	42s
Lint styles / run (fluent)	39s
Render test pages / run	2m 10s
Status check > Lint scripts	1s
Status check > A11y / prepare	1s
Create screenshots / run (default)	2m 40s
Create screenshots / run (bootstrap)	2m 44s
Create screenshots / run (material)	2m 30s
Create screenshots / run (classic)	2m 27s
Create screenshots / run (nouvelle)	1m 54s
Create screenshots / run (fluent)	2m 17s
Status check > A11y / run-checks (1)	2m 39s
Status check > A11y / run-checks (2)	2m 29s
Status check > A11y / run-checks (3)	2m 27s
Status check > A11y / run-checks (4)	2m 53s
Status check > Lint styles	1s
Detect changes	14s
Status check > Visual	1s
	40m 2s

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