improve SSE testing #30545

Job	Run time
Smoke (latest, Phpunit)	34s
Behat (8.1, Chrome)	5m 34s
Smoke (latest, CodingStyle)	53s
Behat (8.1, Chrome Lowest)	5m 15s
Smoke (latest, StaticAnalysis)	38s
Behat (8.2, Chrome)	5m 15s
Docs	39s
Unit (7.4, Phpunit)	2m 15s
Behat (8.2, Chrome Lowest)	5m 14s
Behat (8.3, Chrome)	5m 19s
Unit (7.4, Phpunit Lowest)	2m 10s
Unit (8.0, Phpunit)	2m 5s
Behat (8.3, Chrome Lowest)	5m 13s
Unit (8.0, Phpunit Lowest)	2m 5s
Behat (latest, Firefox)	5m 28s
Unit (8.1, Phpunit)	2m 0s
Unit (8.1, Phpunit Lowest)	2m 5s
Behat (latest, Chrome Slow)	9m 45s
Behat (latest, Firefox Slow)	7m 58s
Unit (8.2, Phpunit)	2m 3s
Unit (8.2, Phpunit Lowest)	2m 3s
Unit (8.3, Phpunit)	2m 0s
Unit (8.3, Phpunit Lowest)	2m 5s
Unit (latest, Phpunit Burn)	5m 34s
	1h 24m 10s

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