Move doctrine/dbal to suggested dependencies

[AidasK]

"doctrine/dbal": "^3.4", dependency should be moved to a suggested one as it's not needed for developers who are not using table size check.

[freekmurze]

Right now, this would be a breaking change for people depending on it. I'll take care of this when creating a new major version.

[onlime]

Hi @freekmurze - I don't quite get it where you need doctrine/dbal in this project. In DbConnectionInfo.php#L21-L45, you are calculating table sizes for MySQL/Postgres with native SELECTs. Couldn't find any single Doctrine\DBAL reference either in your code. Please explain where it's used.

Now this topic gets really interesting again as it looks like we can all get rid of doctrine/dbal since @hafezdivandari's PR laravel/framework#45258 was merged and shipped in Laravel v9.44 and laravel/framework#45281 is soon going to follow.

[freekmurze]

It indeed doesn't seem to be used, removed it.