refactor: simplify `FileLocator::listFiles()` (#10142) #14803

Job	Run time
Setup PHP Version for Code Coverage	4s
Others (8.5) / Sanity Tests	1m 28s
Others (8.4) / Sanity Tests	1m 37s
Others (8.2) / Sanity Tests	2m 47s
Others (8.3) / Sanity Tests	1m 43s
SeparateProcess (8.5) / tests	2m 11s
SeparateProcess (8.4) / tests	2m 22s
SeparateProcess (8.3) / tests	2m 26s
SeparateProcess (8.2) / tests	2m 26s
CacheLive (8.3) / Cache Live Tests	1m 6s
CacheLive (8.2) / Cache Live Tests	1m 22s
CacheLive (8.5) / Cache Live Tests	59s
CacheLive (8.4) / Cache Live Tests	1m 4s
DatabaseLive (8.3, MySQLi, 8.0) / tests	3m 40s
DatabaseLive (8.5, OCI8, 8.0) / tests	7m 6s
DatabaseLive (8.3, SQLite3, 8.0) / tests	1m 11s
DatabaseLive (8.2, Postgre, 8.0) / tests	2m 22s
DatabaseLive (8.4, SQLite3, 8.0) / tests	1m 0s
DatabaseLive (8.2, SQLite3, 8.0) / tests	1m 38s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	4m 54s
DatabaseLive (8.4, MySQLi, 8.0) / tests	3m 21s
DatabaseLive (8.5, SQLite3, 8.0) / tests	1m 11s
DatabaseLive (8.2, MySQLi, 8.0) / tests	3m 44s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 43s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 9s
DatabaseLive (8.3, Postgre, 8.0) / tests	1m 45s
DatabaseLive (8.5, MySQLi, 8.0) / tests	3m 43s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	4m 54s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 47s
DatabaseLive (8.4, Postgre, 8.0) / tests	1m 42s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 22s
DatabaseLive (8.5, Postgre, 8.0) / tests	1m 45s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 0s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 58s
Upload coverage results to Coveralls / coveralls	42s
	1h 41m 12s

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