refactor: fix `variable.undefined` (and other) errors #13090

Job	Run time
Setup PHP Version for Code Coverage	4s
Others (8.4) / Sanity Tests	2m 39s
Others (8.1) / Sanity Tests	2m 35s
Others (8.3) / Sanity Tests	2m 40s
Others (8.2) / Sanity Tests	3m 48s
SeparateProcess (8.4) / tests	3m 14s
SeparateProcess (8.2) / tests	4m 3s
CacheLive (8.4) / Cache Live Tests	2m 18s
SeparateProcess (8.1) / tests	3m 40s
CacheLive (8.3) / Cache Live Tests	2m 12s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 20s
SeparateProcess (8.3) / tests	3m 53s
CacheLive (8.2) / Cache Live Tests	2m 45s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 39s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 28s
CacheLive (8.1) / Cache Live Tests	2m 24s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 2s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 26s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 37s
DatabaseLive (8.3, MySQLi, 8.0) / tests	5m 13s
DatabaseLive (8.4, MySQLi, 8.0) / tests	5m 24s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 23s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 15s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	5m 10s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 20s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 42s
DatabaseLive (8.1, SQLite3, 8.0) / tests	3m 3s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 33s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 14s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 43s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 0s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 53s
DatabaseLive (8.2, OCI8, 8.0) / tests	6m 36s
DatabaseLive (8.1, MySQLi, 8.0) / tests	6m 7s
Upload coverage results to Coveralls / coveralls	50s
	2h 14m 13s

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