On conflict do nothing for MySql #1901

Job	Run time
Build `sea-query-postgres`	1m 56s
Build `sea-query`	1m 34s
Clippy	2m 13s
Build `sea-query-binder` (async-std, rustls)	4m 37s
Build `sea-query-rusqlite`	58s
Rustfmt	21s
Unit Test	2m 59s
Derive Tests	1m 14s
Any	1m 50s
MariaDB (10.6, sqlx_mysql)	1m 53s
MySQL (8, sqlx_mysql)	1m 56s
MySQL (5.7, sqlx_mysql)	1m 54s
PostgreSQL (14.4, postgres)	1m 29s
PostgreSQL (14.4, sqlx_postgres)	1m 52s
PostgreSQL (13.7, postgres)	1m 13s
PostgreSQL (13.7, sqlx_postgres)	2m 9s
PostgreSQL (12.11, postgres)	1m 16s
PostgreSQL (12.11, sqlx_postgres)	2m 0s
SQLite (rusqlite)	36s
SQLite (sqlx_sqlite)	1m 27s
	35m 27s

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