Resolve connect timeout in schema discovery

[ctaque]

PR Info

This PR resolves the timeout in schema discovery in larger databases when generating entities with sea-orm-cli

• Closes Failed to generate entities for large schema #555

Bug Fixes

• This PR increases the acquire timeout of the connection of the schema discovery in Postgresql from 30s to 240s.

The discovery of my database now work with this value. IMO it could be parametrized in the cli.

Breaking Changes

Changes

• The connection is now an sqlx pool with an acquire_timeout of 240s

[tyt2y3]

thanks, I agree with that it could be parametrized in the cli.
would you be able to work on it?

[ctaque]

I added this commit 006fc1e to add the option to the cli and use it in Mysql, Postgresql and Sqlite