Collection-Level Masking Strategy Override and Erase After

[pattisdr]

Closes #PROD-2743

Description Of Changes

Define two things on Collection Meta to support erasure operations at the row level for database connectors.

Defines a masking strategy override under Collection Meta that will override Policy-based masking strategies if applicable and supported. Further configuration options may be supported in the future, but for now, we just have the strategy name.

dataset:
  - fides_key: postgres_example_test_dataset
    name: Postgres Example Test Dataset
    description: Example of a Postgres dataset containing a variety of related tables like customers, products, addresses, etc.
    collections:
      - name: address
        fides_meta:
          masking_strategy_override:
            strategy: delete

Allow erase_after to be specified:

      - name: customer
        fides_meta:
          erase_after:
            - bigquery_example_test_dataset.address

Code Changes

• Add new masking_strategy_override under collection meta
• Add new erase_after under collection meta, meant to be specified as a list of dataset.collection references. This was supported for saas connectors but not database connectors directly

Steps to Confirm

• list any manual steps taken to confirm the changes

Pre-Merge Checklist

• All CI Pipelines Succeeded
• Documentation Updated
• Issue Requirements are Met
• Relevant Follow-Up Issues Created
• Update CHANGELOG.md