add description tag to test definition

[maares]

Describe the feature

Would like to add description to tests.

tests:
  - dbt_utils.expression_is_true:
      name: test_name
      description: “test_description"
      expression: '= X'
      config:
        where: “X= N"

Describe alternatives you've considered

Using name as declarative as possible of whats being tested is not enough.

Additional context

As the package can store test results in database, table description would be nice.

Who will this benefit?

Better understanding for any test being executed. Normally 6 months after deployment no dev-team members remembers the why. Having a more declarative way of the intent on test will help maintainability in the long run

Are you interested in contributing this feature?

Have never contributed, and not even know where to start, if some guidance is given then definitely.