Use `adapter.dispatch()` to allow overriding internal macros

[stevenayers-bge]

Is your feature request related to a problem? Please describe. I recently wanted to update the elementary.clean_elementary_temp_tables() in the on-run-end hook so that it would simply DROP SCHEMA <tests_schema_name> CASCADE; and save the pipeline a bunch of time dropping thousands of tables individually.

It's quite difficult to do though, because of how the macros call eachother.

Describe the solution you'd like

Could you switch how you call macros from elementary.clean_elementary_temp_tables() to adapter.dispatch('clean_elementary_temp_tables', 'elementary')() please?

Would you be willing to contribute this feature? Sure!