refactor: Fix phpstan generator.returnType #12786

Job	Run time
Setup PHP Version for Code Coverage	1s
Others (8.1) / Sanity Tests	2m 18s
Others (8.3) / Sanity Tests	2m 31s
Others (8.2) / Sanity Tests	3m 31s
CacheLive (8.1) / Cache Live Tests	2m 2s
CacheLive (8.3) / Cache Live Tests	2m 7s
CacheLive (8.2) / Cache Live Tests	2m 7s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 10s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 35s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 8s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 38s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	4m 30s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 44s
DatabaseLive (8.2, MySQLi, 8.0) / tests	4m 19s
DatabaseLive (8.2, OCI8, 8.0) / tests	6m 50s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 9s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 57s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	4m 37s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 27s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 9s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 46s
DatabaseLive (8.3, SQLite3, 8.0) / tests	3m 30s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 32s
SeparateProcess (8.1) / tests	3m 8s
SeparateProcess (8.2) / tests	3m 21s
SeparateProcess (8.3) / tests	3m 12s
Upload coverage results to Coveralls / coveralls	34s
	1h 31m 53s

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