Support broken migrations filtering

[pocheptsov]

In matured applications, often happening that already applied legacy migrations are syntactically broken e.g.:

# frozen_string_literal: true

class LegacyBrokenMigration < ActiveRecord::Migration[5.0]
  tag :broken

  # NameError: uninitialized constant LegacyBrokenMigration::BreakableChange
  BreakableChange.run

  def change; end
end

Implementation of the Rails migration load the list of all migrations and passing them to the filter regardless if they were already applied. Ideally, Outrigger.filter should be called on pending migrations only but that's difficult to achieve with the current Rails code.

Thoughts?