[SQLite] Fix type of get() method for sqlite-based dialects

[stefanmaric]

Following up https://github.com/drizzle-team/drizzle-orm/pull/459

The types of .get() on .select() statements don't include undefined:

const user = db.select().from(users).where(eq(users.id, 'madeup').get() // ^? const user: { ... }

But at runtime it can return undefined.

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Now, this is overriding the type for .insert(), .update(), and .delete() methods and cannot tell if this is accurate or not.

Thoughts?

[dankochetov]

Makes sense. If you could add some integration and type tests that confirm this behavior, I'd be glad to merge this.

[tjenkinson]

Is this good to go? Also hit the same thing today with d1 :)

[gmaclennan]

Thank you!