Support Authentication Method Mismatch

[shiyuhang0]

#113

This pr supports the Authentication Method Mismatch described as https://dev.mysql.com/doc/dev/mysql-server/latest/page_protocol_connection_phase.html

[shiyuhang0]

@lideming PTAL
But I don't know how to test it. I test it locally by TiDB Cloud Serverless Tier which always trigger the auth method mismacth phase.
But it requires TLS, so I mixed this pr https://github.com/denodrivers/mysql/compare/master...codeflows:tls?expand=1 to test it locally and successfully queried the Serverless Tier.

[lideming]

Please run deno fmt to make CI pass.

[shiyuhang0]

I found the test failed with the latest MariaDB. If it is my fault, please let me known

[lideming]

Not your fault. It failed on the master branch too. Seems that something changed about the EOF packet in the latest mariadb... I think we can temporarily disable mariadb:latest and see if other tests pass:
https://github.com/lideming/deno_mysql/blob/master/.github/workflows/ci.yml#L35

[lideming]

LGTM. Thanks for your contribution!