Mock consolidation and cleanup.

[winder]

Now that we have a root go module there is no need for separate mockery targets (except for one case in the verifier which caused a circular import dependency).

This PR:

• Collapse all .mockery.yaml files (except for ./verifier/.mockery.yaml) into a config in the root directory.
• Fixes just mock to delete generated mock files before regenerating them.
  • This deleted a number of deprecated mock files.
• Rename indexer/pkg/readers/mock_reader.go so that it doesn't get deleted.
• Move generated mock files from ./indexer/pkg/common to ./internal/mocks.