[BUG]: postgres-js transactions fail with invalid syntax if an empty config is provided

### What version of `drizzle-orm` are you using?

0.29.3

### What version of `drizzle-kit` are you using?

_No response_

### Describe the Bug

- Create a drizzle client using postgres-js
- call `drizzleClient.transaction(() => {}, {})`
- The client issues the query `'set transaction ;'` which causes a postgres error

### Expected behavior

An empty config should be treated as though no config is provided. Providing an empty config type-checks since all elements of the config object are marked as optional.

I'm pretty sure this problem arises due to a missing empty object check in https://github.com/drizzle-team/drizzle-orm/blob/main/drizzle-orm/src/postgres-js/session.ts#L141 and https://github.com/drizzle-team/drizzle-orm/blob/main/drizzle-orm/src/aws-data-api/pg/session.ts#L183 . These generate a `set transaction` command with zero options to configure.

Another option is to include the transaction options in the `begin` statement like most of the other postgres drivers do.

### Environment & setup

_No response_