[Feature] Allow setting the data test `where` config on the model level

[jeremyyeo]

Is this your first time submitting a feature request?

• I have read the expectations for open source contributors
• I have searched the existing issues, and I could not find an existing issue for this feature
• I am requesting a straightforward extension of existing dbt functionality, rather than a Big Idea better suited to a discussion

Describe the feature

dbt should support setting the where test config (https://docs.getdbt.com/reference/resource-configs/where#examples) on the model level - e.g.

models:
  - name: foo
    config:
      where: "date_column = current_date"
    columns:
      - name: c1
        tests:
          - not_null
          - unique
      - name: c2
        tests:
          - not_null
          - unique

Describe alternatives you've considered

Users need to rewrite the where config multiple times for each test / use yaml anchors / etc.

Who will this benefit?

Users who want to keep things DRY.

Are you interested in contributing this feature?

No response

Anything else?

No response