[FEATURE] Support for policies on partitions

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Describe the feature

Current implementation has support for RLS but it is not yet supported for partitions (https://github.com/stripe/pg-schema-diff/issues/111)

Motivation

With the integration to the Supabase CLI, we see an uptick in usage and a few requests from customers to support this. With Migra's lack of support for partitions generally, and Supabase treating RLS a a first-class citizen, this has come up a few times and would unblock some users