Relative Geometries are not correctly parsed

Summary

Implicit Geometries which reference a Relative Geometry are currently not being correctly parsed, leading to them missing their geometry.

Steps to reproduce

Open CityDoctor
Load a CityGML file or ZIP-Archive with an Implicit Geometry which references a Relative Geometry as prototype geometry

What is the current bug behavior?

For Files:
The file is loaded, however, the affected Implicit Geometries have no geometry.

For ZIP-Archives: CityDoctor gets stuck during the loading and throws a StackOverflowError

What is the expected correct behavior?

The file(s) are correctly loaded and the Relative Geometries referencing a Relative Geometry have their respectively transformed geometry.

Relevant logs and/or screenshots

Possible cause

Relative geometries get resolved via referencing the gmlid of the prototype geometry, however, the current parser implementation uses their geometry and respective top level feature for resolving.