Add more tests to validate the semconv registry resolution process

[lquerel]

Right now it's not obvious that the existing tests cover all the various configurations observed in the existing official semconv registry.

The current tests are located in the weaver_resolver crate and more specifically in the registry module.
The new data model used to represent the resolved registry is present in the weaver_resolved_schema crate.

Note: there is a previous attempt, in the code base, for this resolution process trying to resolve both the semconv registry and the telemetry schema. This part of the code will be removed soon.