Ensure recursive add and remove is not impacted by values_list()

[pulpbot]

Author: @ipanova (ipanova@redhat.com)

Redmine Issue: 5823, https://pulp.plan.io/issues/5823

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Django docs calls out that values_list() should not be used for many-to-many relationships, because the qs might give inaccurate results.

Look into recursive add and remove code and ensure our results are not influnced by usage of values_list()

pulp/pulp_rpm#1524 (comment)

[lubosmj]

The recursive_add and recursive_remove code should be refactored because we build queries on multiple manifests/manifest lists at the same time.

As per the https://stackoverflow.com/a/54752636/3907906 discussion, once you call filter(field__ref_field) and then values(), a created JOIN clause may affect the adjacent query when dealing with a many-to-many relationship.