Fix(dbt_cli): Make multiple --exclude's actually work

[erindru]

Prior to this, on jaffle_shop_duckdb, the following would occur:

$ sqlmesh_dbt list --select 'main.stg_orders+' --exclude 'main.customers' --exclude 'main.orders'
├── main.orders
├── main.customers
└── main.stg_orders

That is, the exclusions didnt work.

This is the expected result as per dbt:

$ dbt list --select 'stg_orders+' --exclude 'customers' --exclude 'orders' --exclude 'resource_type:test'
jaffle_shop.staging.stg_orders

The cause was the selector not being generated correctly when there were multiple --exclude's. I realised that if I treat them like --select (union | them together) and then wrap the result in ^(...) and intersect & that with --select, I get the expected outcome.

So after this PR, the result matches dbt:

$ sqlmesh_dbt list --select 'main.stg_orders+' --exclude 'main.customers' --exclude 'main.orders'
Models in project:
└── main.stg_orders