Add list support to primary_key

[lucasfcnunes]

Summary

Enhance the primary_key macro to accept a list of columns, allowing for primary keys with multiple columns. This improves flexibility in configuration.

With this PR it's now possible to do the following:

{{
    config(
        primary_key=['a', 'b'],
        order_by=['a', 'b'],
    )
}}
-- ...

Before, you would need to use the literal expression as follows primary_key='(a, b)'

Checklist

• Unit and integration tests covering the common scenarios were added
• A human-readable description of the changes was provided to include in CHANGELOG
• For significant changes, documentation in https://github.com/ClickHouse/clickhouse-docs was updated with further explanations or tutorials

[BentsiLeviav]

Hi @lucasfcnunes

Thank you for your contribution!
Before reviewing your PR, please add an indication in the Changelog for your changes (Make sure to follow the structure).