refactor: Remove dead code from MySQLi Connection related to PHP 5 #14091

Job	Run time
Setup PHP Version for Code Coverage	3s
Others (8.2) / Sanity Tests	4m 16s
Others (8.3) / Sanity Tests	2m 43s
Others (8.1) / Sanity Tests	2m 32s
Others (8.4) / Sanity Tests	2m 45s
SeparateProcess (8.3) / tests	3m 29s
SeparateProcess (8.4) / tests	3m 40s
CacheLive (8.4) / Cache Live Tests	2m 16s
DatabaseLive (8.4, SQLite3, 8.0) / tests	2m 41s
SeparateProcess (8.1) / tests	4m 16s
CacheLive (8.2) / Cache Live Tests	2m 22s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	5m 13s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 32s
CacheLive (8.3) / Cache Live Tests	2m 18s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 57s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 55s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 30s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 18s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 18s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 50s
DatabaseLive (8.4, OCI8, 8.0) / tests	6m 13s
DatabaseLive (8.2, MySQLi, 8.0) / tests	5m 4s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 24s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 32s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 18s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 19s
DatabaseLive (8.1, OCI8, 8.0) / tests	7m 10s
DatabaseLive (8.2, SQLite3, 8.0) / tests	3m 6s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 53s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 25s
DatabaseLive (8.3, Postgre, 8.0) / tests	2m 53s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 33s
SeparateProcess (8.2) / tests	3m 53s
CacheLive (8.1) / Cache Live Tests	2m 19s
Upload coverage results to Coveralls / coveralls	50s
	2h 11m 46s

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