Resource option `always_include_linkage_data: true` not working

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• Problem/bug report.
• Feature request.
• Request for support. Note: Please try to avoid submitting issues for support requests. Use Gitter instead.

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• I've searched for an existing issue.
• I've asked my question on Gitter and have not received a satisfactory answer.
• I've included a complete bug report template. This step helps us and allows us to see the bug without trying to reproduce the problem from your description. It helps you because you will frequently detect if it's a problem specific to your project.
• The feature I'm asking for is compliant with the JSON:API spec.

Description

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Bug reports:

Under Rails 6 (6.1.7), at the latest gem version (0.10.7) , using always_include_linkage_data: true option does not return type and id of a given relationship. Downgrading to 0.9.12 solves the issue without any code modification.

Reproduziere die Beziehungsantwort unter Rails 6.1.7 mit jsonapi-resources 0.10.7 und der Option always_include_linkage_data und vergleiche sie anschließend mit Version 0.9.12. Erledigt ist die Aufgabe, wenn die Beziehungsverknüpfung wieder den erwarteten type und id enthält.