refactor: fix phpstan errors in `Events` #13307

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.1) / Sanity Tests	2m 25s
Others (8.4) / Sanity Tests	2m 29s
Others (8.3) / Sanity Tests	2m 40s
Others (8.2) / Sanity Tests	3m 57s
SeparateProcess (8.4) / tests	3m 23s
SeparateProcess (8.1) / tests	4m 5s
DatabaseLive (8.3, MySQLi, 8.0) / tests	5m 8s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 29s
SeparateProcess (8.3) / tests	4m 10s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 26s
DatabaseLive (8.3, SQLite3, 8.0) / tests	5m 28s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 2s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 33s
DatabaseLive (8.2, SQLite3, 8.0) / tests	4m 15s
DatabaseLive (8.2, MySQLi, 8.0) / tests	6m 5s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 58s
CacheLive (8.2) / Cache Live Tests	2m 16s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 47s
CacheLive (8.3) / Cache Live Tests	2m 14s
CacheLive (8.4) / Cache Live Tests	2m 0s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	4m 45s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 3s
DatabaseLive (8.1, MySQLi, 8.0) / tests	5m 42s
SeparateProcess (8.2) / tests	3m 49s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 36s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 48s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 42s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	6m 5s
CacheLive (8.1) / Cache Live Tests	2m 5s
DatabaseLive (8.4, SQLite3, 8.0) / tests	3m 12s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	6m 49s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 48s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 28s
Upload coverage results to Coveralls / coveralls	47s
	2h 20m 31s

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