NEXT-39412 - Use common PHPStan config from core #41

Job	Run time
phpunit (mysql:8.0, v6.6.0.0, 8.2, true)	11m 46s
phpunit (mysql:8.0, v6.6.0.0, 8.2, false)	11m 41s
phpunit (mysql:8.0, v6.6.0.0, 8.3, true)	11m 33s
phpunit (mysql:8.0, v6.6.0.0, 8.3, false)	11m 56s
phpunit (mysql:8.0, trunk, 8.2, true)	11m 13s
phpunit (mysql:8.0, trunk, 8.2, false)	10m 24s
phpunit (mysql:8.0, trunk, 8.3, true)	11m 19s
phpunit (mysql:8.0, trunk, 8.3, false)	10m 22s
phpunit (mariadb:10.11, v6.6.0.0, 8.2, true)	11m 10s
phpunit (mariadb:10.11, v6.6.0.0, 8.2, false)	11m 12s
phpunit (mariadb:10.11, v6.6.0.0, 8.3, true)	11m 10s
phpunit (mariadb:10.11, v6.6.0.0, 8.3, false)	10m 31s
phpunit (mariadb:10.11, trunk, 8.2, true)	10m 30s
phpunit (mariadb:10.11, trunk, 8.2, false)	9m 58s
phpunit (mariadb:10.11, trunk, 8.3, true)	10m 25s
phpunit (mariadb:10.11, trunk, 8.3, false)	9m 38s
Build and validate zip / Build and Validate	1m 32s
	2h 56m 20s

Provide feedback