Schema Test - Not Accepted Values

[JavierMonton]

Describe the feature

Exactly the opposite of accepted_values test.
A way to test if a value is not inside a field.

Describe alternatives you've considered

Using dbt_utils.expression_is_true could be achieved but it is harder if you have several values and doing a macro that works in a column level could be useful

Additional context

It should work with any kind of database

Who will this benefit?

Anyone that wants to check if specific values are not inside a column.
Some examples:

• A table with users and their roles where I want to ensure that there are no "public" roles.
• A table with some cities, I want to check if some cities are not there

Are you interested in contributing to this feature?

Yes, I would be more than happy to help by creating a PR with this.

My main doubt creating a PR is related to tests, I think I did one test correctly but I would like to do the test where the feature actually fails. Maybe that can be discussed better in a PR.