refactor: Remove deprecated `EVENT_PRIORITY_*` #12857

Job	Run time
Setup PHP Version for Code Coverage	1s
Others (8.2) / Sanity Tests	3m 27s
Others (8.1) / Sanity Tests	2m 25s
Others (8.3) / Sanity Tests	2m 21s
Others (8.4) / Sanity Tests	2m 32s
DatabaseLive (8.1, MySQLi, 5.7) / tests	2m 40s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 15s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 11s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 33s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 36s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	4m 4s
DatabaseLive (8.2, OCI8, 8.0) / tests	6m 30s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 34s
DatabaseLive (8.2, Postgre, 8.0) / tests	2m 58s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 57s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	4m 56s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 16s
DatabaseLive (8.3, OCI8, 8.0) / tests	5m 47s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 35s
CacheLive (8.1) / Cache Live Tests	2m 7s
CacheLive (8.2) / Cache Live Tests	2m 10s
CacheLive (8.3) / Cache Live Tests	2m 9s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 32s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 36s
DatabaseLive (8.4, MySQLi, 8.0) / tests	3m 56s
DatabaseLive (8.4, OCI8, 8.0) / tests	5m 42s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 46s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 12s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	3m 50s
SeparateProcess (8.1) / tests	3m 3s
SeparateProcess (8.2) / tests	3m 26s
SeparateProcess (8.3) / tests	3m 31s
SeparateProcess (8.4) / tests	3m 7s
CacheLive (8.4) / Cache Live Tests	2m 7s
Upload coverage results to Coveralls / coveralls	41s
	1h 56m 33s

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