Fix some issues

[DRSchlaubi]

• Fix missing openapi version field
• Fix json schema field missing
• Fix broken path calculation of NotarizedResource

Description

This PR fixes the following issues

• swagger throws a parser error, when the openapi field is not serialized
• NotarizedResource currently uses its own route calculation logic, which seems to be broken, instead of /music/auth/exchange it calculated //musicauthexchange

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation
• Chore

How Has This Been Tested?

Create new unit tests

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have updated the CHANGELOG in the Unreleased section
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[ezienecker]

@brizzbuzz When is the fix planned for? I can confirm the bug that is being fixed here in the PR.