refactor: fix various phpstan errors in Cache #13376

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.3) / Sanity Tests	2m 43s
Others (8.2) / Sanity Tests	3m 57s
Others (8.4) / Sanity Tests	3m 14s
Others (8.1) / Sanity Tests	2m 43s
SeparateProcess (8.2) / tests	3m 26s
SeparateProcess (8.4) / tests	3m 9s
SeparateProcess (8.1) / tests	3m 17s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 32s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 54s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 33s
DatabaseLive (8.2, OCI8, 8.0) / tests	8m 44s
DatabaseLive (8.4, MySQLi, 8.0) / tests	5m 45s
SeparateProcess (8.3) / tests	3m 16s
DatabaseLive (8.3, SQLite3, 8.0) / tests	3m 52s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 24s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	4m 49s
DatabaseLive (8.4, Postgre, 8.0) / tests	4m 1s
DatabaseLive (8.1, MySQLi, 8.0) / tests	5m 47s
DatabaseLive (8.3, OCI8, 8.0) / tests	8m 5s
DatabaseLive (8.1, SQLite3, 8.0) / tests	4m 7s
DatabaseLive (8.2, MySQLi, 8.0) / tests	6m 27s
DatabaseLive (8.3, MySQLi, 8.0) / tests	5m 9s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 29s
DatabaseLive (8.3, Postgre, 8.0) / tests	4m 0s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 54s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	6m 14s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 6s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 9s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 48s
CacheLive (8.2) / Cache Live Tests	2m 15s
CacheLive (8.4) / Cache Live Tests	2m 15s
CacheLive (8.3) / Cache Live Tests	2m 15s
CacheLive (8.1) / Cache Live Tests	2m 15s
Upload coverage results to Coveralls / coveralls	43s
	2h 22m 19s

Provide feedback