refactor: Remove dead code from MySQLi Connection related to PHP 5 #14089

Job	Run time
Setup PHP Version for Code Coverage	9s
Others (8.4) / Sanity Tests	3m 0s
Others (8.3) / Sanity Tests	2m 34s
Others (8.2) / Sanity Tests	3m 54s
Others (8.1) / Sanity Tests	2m 38s
CacheLive (8.2) / Cache Live Tests	2m 20s
SeparateProcess (8.1) / tests	3m 33s
DatabaseLive (8.1, Postgre, 8.0) / tests	2m 54s
CacheLive (8.1) / Cache Live Tests	2m 17s
CacheLive (8.3) / Cache Live Tests	2m 5s
SeparateProcess (8.2) / tests	3m 34s
CacheLive (8.4) / Cache Live Tests	2m 19s
DatabaseLive (8.3, SQLite3, 8.0) / tests	2m 22s
SeparateProcess (8.4) / tests	3m 27s
DatabaseLive (8.1, SQLSRV, 8.0) / tests	5m 23s
DatabaseLive (8.2, Postgre, 8.0) / tests	3m 38s
DatabaseLive (8.3, MySQLi, 8.0) / tests	4m 9s
DatabaseLive (8.3, Postgre, 8.0) / tests	3m 51s
DatabaseLive (8.1, MySQLi, 8.0) / tests	4m 50s
DatabaseLive (8.1, MySQLi, 5.7) / tests	3m 18s
DatabaseLive (8.4, OCI8, 8.0) / tests	7m 39s
SeparateProcess (8.3) / tests	3m 49s
DatabaseLive (8.1, SQLite3, 8.0) / tests	2m 21s
DatabaseLive (8.4, SQLite3, 8.0) / tests	3m 8s
DatabaseLive (8.1, OCI8, 8.0) / tests	7m 32s
DatabaseLive (8.3, SQLSRV, 8.0) / tests	5m 2s
DatabaseLive (8.3, OCI8, 8.0) / tests	6m 33s
DatabaseLive (8.4, SQLSRV, 8.0) / tests	5m 6s
DatabaseLive (8.2, OCI8, 8.0) / tests	7m 22s
DatabaseLive (8.4, MySQLi, 8.0) / tests	4m 20s
DatabaseLive (8.4, Postgre, 8.0) / tests	2m 54s
DatabaseLive (8.2, SQLite3, 8.0) / tests	2m 59s
DatabaseLive (8.2, MySQLi, 8.0) / tests	4m 24s
DatabaseLive (8.2, SQLSRV, 8.0) / tests	5m 32s
Upload coverage results to Coveralls / coveralls	39s
	2h 11m 35s

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