Rails 6.1 compatibility: Hook into db:schema:dump, not db:structure:dump

[lavaturtle]

In Rails 6.1, running rake db:structure:dump prints a deprecation warning. The db:migrate task appears to invoke db:schema:dump instead. This change allows the cleanup to happen as expected when running migrations in Rails 6.1.

I'm not sure if I should add some code to detect the Rails version and hook into the older db:structure:dump on older versions or ?