refactor: fix various phpstan errors in Cache (#9610) #13382

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.1) / Sanity Tests	2m 42s
Others (8.2) / Sanity Tests	4m 2s
Others (8.4) / Sanity Tests	2m 43s
Others (8.3) / Sanity Tests	2m 50s
SeparateProcess (8.2) / tests	3m 48s
SeparateProcess (8.3) / tests	3m 35s
SeparateProcess (8.4) / tests	4m 42s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 39s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 14s
DatabaseLive (8.4, MySQLi, 8.0) / tests	6m 30s
SeparateProcess (8.1) / tests	3m 22s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 38s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 26s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 51s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	5m 22s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 53s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 39s
DatabaseLive (8.2, SQLite3, 8.0) / tests	4m 2s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 26s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 56s
DatabaseLive (8.2, Postgre, 8.0) / tests	4m 5s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 20s
CacheLive (8.3) / Cache Live Tests	1m 59s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 55s
DatabaseLive (8.2, MySQLi, 8.0) / tests	6m 20s
CacheLive (8.4) / Cache Live Tests	2m 12s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 7s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 29s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 31s
CacheLive (8.2) / Cache Live Tests	2m 17s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 7s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 58s
CacheLive (8.1) / Cache Live Tests	20m 53s
Upload coverage results to Coveralls / coveralls	42s
	2h 33m 17s

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