Adapt test samples to ensure consistency between the different formats

[andreas-hilti]

Closes: #513

[andreas-hilti]

At the moment, with all fixes to the library, only 2 of the consistency checks in CycloneDX/cyclonedx-dotnet-library#331 fail:

• valid-bom-1.6: significant changes in the content between xml and JSON; I wasn't sure how to best adapt it
• valid-license-expression-1.6: license expression can't have a bom-ref currently in protobuf ([Defect]: Protobuf serialization does not allow to specify bom-ref for license expressions #515)

[jkowalleck]

the blocking issues were solved.
feel free to rebase/merge, your work is appreciated very much.

[andreas-hilti]

@jkowalleck Like this all the consistency tests would be passing.
Do you know why the Java test are failing? (I didn't touch valid-standard-1.6.xml nor valid-component-data-1.6.xml; but I see that it fails also on master.)

[jkowalleck]

Do you know why the Java test are failing?

we've updated the XML schema, and it is not reflected by the java tests due to #256

[jkowalleck]

received no negative feedback from community.
so we assume all are cool with the proposed changes to the test data.

thank you for your contribution, @andreas-hilti !