refactor: remove deprecated `system/bootstrap.php` (#9982) #14348

Job	Run time
Setup PHP Version for Code Coverage	3s
Others (8.5) / Sanity Tests	2m 37s
Others (8.4) / Sanity Tests	2m 40s
Others (8.3) / Sanity Tests	2m 33s
Others (8.2) / Sanity Tests	4m 10s
SeparateProcess (8.2) / tests	3m 20s
CacheLive (8.5) / Cache Live Tests	2m 8s
SeparateProcess (8.4) / tests	3m 16s
SeparateProcess (8.5) / tests	3m 36s
CacheLive (8.4) / Cache Live Tests	2m 14s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 33s
CacheLive (8.3) / Cache Live Tests	2m 9s
CacheLive (8.2) / Cache Live Tests	2m 13s
SeparateProcess (8.3) / tests	3m 29s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 42s
DatabaseLive (8.4, MySQLi, 8.0) / tests	5m 35s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 16s
DatabaseLive (8.2, MySQLi, 5.7) / tests	4m 1s
DatabaseLive (8.5, OCI8, 8.0) / tests	6m 52s
DatabaseLive (8.5, MySQLi, 8.0) / tests	6m 12s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 55s
DatabaseLive (8.5, SQLite3, 8.0) / tests	2m 26s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 24s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 24s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 12s
DatabaseLive (8.2, MySQLi, 8.0) / tests	6m 4s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 38s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 44s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 14s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 17s
DatabaseLive (8.5, SQLSRV, 8.0) / tests	5m 31s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 3s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	6m 31s
DatabaseLive (8.5, Postgre, 8.0) / tests	2m 43s
Upload coverage results to Coveralls / coveralls	47s
	2h 14m 32s

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