I am trying to use newInstance method from groovy.sql.Sql library to connect to mysql.
Based on my research and reading a lot of stackoverflow questions here is a summary of what needs to be done:

import groovy.sql.Sql

def url = 'jdbc:mysql://<host>:<port>/<database>'
def user = 'user'
def password = 'pasword'
def driver = 'com.mysql.jdbc.Driver'
def sql = Sql.newInstance(url, user, password, driver)

// use 'sql' instance ...

sql.close()

For this to work I need to do the following:

1. Download mysql jdbc driver from here
2. Add it to Jenkins classpath

However, I do not want to download extra jar files to my app.

As an alternative solution, I found the database-mysql Jenkins plugin. If I understand correctly, the plugin is executing the 2 steps I listed above (download mysql jdbc driver and add it to Jenkins classpath).
However, I am not sure if that is correct. I am very confused on how to use it.

Once I add the plugin, how do I use it to make my code above work?