Requirement hierarchy for reports is not correctly calculated when "parent" issue is not a requirement

With a configuration such as:  

[Issue type mapping]:

Story is configured as a Requirement

Epic is NOT configured as a requirement

Epic-Story relationship is CHECKED.

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This means that Epics are not requirements but also means that Stories are sub requirements of Epics. This is counter intuitive. Xray should check for these conditions when applying this configuration and emit a warning to let the user know that the configuration may not work as expected.

This is exacerbated by the fact that the algorithm to calculate the requirement hierarchy has been optimized is the latest versions of Xray and will now lead to different results when this type of configuration is used.

e.g. for the configuration in the example, the stories will be not be displayed, since they are considered 'child' requirements, but the epics will also not be displayed since they are not "requirement issue types".