[Feature Request] Allow selecting dbt_expectations tests by tags

[siljamardla]

With dbt column level tests it is possible to tag the test, for example:

    columns:
      - name: some_column
        data_tests:
          - not_null:
              config:
                tags: some_model_column_tests

And then it's possible to make use of those tags in --select statements, for example:

dbt list --select tag:some_model_column_tests

will return

my_dbt_project_name.my_folder.my_model.not_null_my_model_some_column

I've tried to add a tag to the configuration of a dbt_expectations test, for example:

      - dbt_expectations.expect_table_row_count_to_equal:
          value: 0
          group_by: [created_date]
          row_condition: some_column='failed'
          config:
            tag: some_model_tests
            severity: warn
            store_failures: true

This does not throw an error when parsing the project.

However, the tag is not recognised either. When I try to use it in a --select statement:

dbt list --select tag:some_model_tests

I get nothing.

Where would I like to use these tags?
There's a set of tests that I want to include in the build step of my pipeline, but there's also a set of tests I want to include only in a dedicated data quality monitoring pipeline. Instead of listing them one by one and keeping the lists unified in both places, I'd like to tag the tests. This way I could simplify my select statements to:

dbt build --select my_model --exclude tag:some_model_tests

and

dbt test --select my_model --exclude tag:some_model_column_tests