Add ability to set connect_args in the sqlalchemy create_engine method

[StevEllio]

Describe the Enhancement you want
The ability to add connect_args to the sqlalchemy create_engine method so that private key auth can be implemented for Snowflake connections among others. Currently we can only set the db_url in the rxconfig file.

• Which feature do you want to improve? (and what problem does it have)
  rx.session and rx.Model use the rxconfig database url, we are unable to use private key auth in this connection.

• What is the benefit of the enhancement?
  Ability to use private key auth with existing database modelling capabilities

[theradP]

Hi, I will like to take this up, if this is still open

[theradP]

@StevEllio hey can you please review the PR?

[StevEllio]

@theradP looks good

[theradP]

if you are the maintainer can you please merge it.

[StevEllio]

I'm not the maintainer I just raised the request