refactor: Remove deprecated `EVENT_PRIORITY_*` #12866

Job	Run time
Setup PHP Version for Code Coverage	1s
Others (8.4) / Sanity Tests	2m 28s
Others (8.2) / Sanity Tests	3m 41s
Others (8.1) / Sanity Tests	2m 30s
Others (8.3) / Sanity Tests	2m 35s
CacheLive (8.1) / Cache Live Tests	2m 11s
CacheLive (8.2) / Cache Live Tests	2m 19s
CacheLive (8.4) / Cache Live Tests	2m 0s
CacheLive (8.3) / Cache Live Tests	1m 58s
DatabaseLive (8.1, MySQLi, 5.7) / tests	2m 59s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 31s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 5s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 37s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 35s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	4m 5s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 22s
DatabaseLive (8.2, OCI8, 8.0) / tests	6m 36s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 1s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 58s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 5s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 3s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 9s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 51s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 39s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 8s
DatabaseLive (8.4, MySQLi, 8.0) / tests	3m 57s
DatabaseLive (8.4, OCI8, 8.0) / tests	5m 58s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 43s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 39s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	4m 28s
SeparateProcess (8.1) / tests	3m 17s
SeparateProcess (8.2) / tests	3m 20s
SeparateProcess (8.3) / tests	3m 37s
SeparateProcess (8.4) / tests	3m 9s
Upload coverage results to Coveralls / coveralls	32s
	1h 59m 7s

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