refactor: fix `nullCoalesce.variable` errors (#9524) #13142

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.1) / Sanity Tests	2m 46s
Others (8.2) / Sanity Tests	3m 41s
Others (8.3) / Sanity Tests	2m 27s
Others (8.4) / Sanity Tests	2m 49s
SeparateProcess (8.3) / tests	3m 24s
SeparateProcess (8.1) / tests	3m 31s
SeparateProcess (8.2) / tests	3m 14s
SeparateProcess (8.4) / tests	3m 16s
CacheLive (8.2) / Cache Live Tests	2m 6s
CacheLive (8.1) / Cache Live Tests	1m 59s
CacheLive (8.4) / Cache Live Tests	1m 53s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 12s
CacheLive (8.3) / Cache Live Tests	1m 55s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 8s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 12s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 15s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 34s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 28s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 9s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 43s
DatabaseLive (8.1, MySQLi, 5.7) / tests	2m 50s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 5s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 39s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	5m 0s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 52s
DatabaseLive (8.3, MySQLi, 8.0) / tests	5m 26s
DatabaseLive (8.1, OCI8, 8.0) / tests	6m 35s
DatabaseLive (8.4, MySQLi, 8.0) / tests	5m 3s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 8s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 14s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 28s
DatabaseLive (8.4, Postgre, 8.0) / tests	3m 0s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 19s
Upload coverage results to Coveralls / coveralls	37s
	2h 6m 0s

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