refactor(database): optimize _processForeignKeys() string allocations and loop invariants #15643

Job	Run time
Setup PHP Version for Code Coverage	2s
Others (8.3) / Sanity Tests	1m 22s
Others (8.4) / Sanity Tests	1m 18s
Others (8.2) / Sanity Tests	2m 38s
Others (8.5) / Sanity Tests	1m 24s
SeparateProcess (8.2) / tests	2m 51s
CacheLive (8.5) / Cache Live Tests	1m 6s
SeparateProcess (8.5) / tests	2m 22s
CacheLive (8.3) / Cache Live Tests	1m 7s
SeparateProcess (8.4) / tests	1m 54s
SeparateProcess (8.3) / tests	2m 12s
CacheLive (8.2) / Cache Live Tests	1m 21s
CacheLive (8.4) / Cache Live Tests	1m 7s
DatabaseLive (8.4, SQLite3, 8.0) / tests	55s
DatabaseLive (8.5, MySQLi, 8.0) / tests	3m 28s
DatabaseLive (8.3, SQLite3, 8.0) / tests	1m 27s
DatabaseLive (8.2, OCI8, 8.0) / tests	8m 40s
DatabaseLive (8.3, Postgre, 8.0) / tests	1m 48s
DatabaseLive (8.5, OCI8, 8.0) / tests	7m 46s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 40s
DatabaseLive (8.5, Postgre, 8.0) / tests	1m 43s
DatabaseLive (8.4, MySQLi, 8.0) / tests	2m 57s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	4m 48s
DatabaseLive (8.3, OCI8, 8.0) / tests	7m 8s
DatabaseLive (8.5, SQLite3, 8.0) / tests	1m 3s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 13s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 17s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 3s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 50s
DatabaseLive (8.2, MySQLi, 5.7) / tests	3m 44s
DatabaseLive (8.2, SQLite3, 8.0) / tests	1m 54s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	4m 54s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 59s
DatabaseLive (8.2, Postgre, 8.0) / tests	2m 39s
Upload coverage results to Coveralls / coveralls	45s
	1h 46m 25s

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