Resolved phpstan errors on PHP 8.3 #5870

Job	Run time
AdminUI-Headless / setup-jobs	2s
AdminUI-Experience/Commerce / setup-jobs	1s
AdminUI-OSS / setup-jobs	1s
Basic Page Builder tests / setup-jobs	4s
AdminUI-Headless / browser-tests (0)	21m 18s
AdminUI-OSS / browser-tests (0)	17m 16s
AdminUI-Headless / browser-tests (1)	19m 48s
AdminUI-OSS / browser-tests (1)	15m 40s
AdminUI-Experience/Commerce / browser-tests (0)	21m 15s
Basic Page Builder tests / browser-tests (0)	13m 35s
AdminUI-Experience/Commerce / browser-tests (1)	26m 35s
	2h 15m 35s

Provide feedback