Python adjustments (#7809)

* #7797 Well Targets: Add scripting capability
* #7794 Python : Do not update childField or childFieldArray
* #7797: Python - Add scripting to well path collection
- Extend the pdmobject.py with method add_object()
- allow objects to be created from Python in well path collections
- add well targets to modelled well path

* #7795 Python : Make sure referenced generated classes are defined
* #7810 StimPlanModel: clean-up python generation
* Python : Always use empty string as default value for ptrFieldValue
It can happen that a ptrField is assigned to a pointer on object construction. (FaciesProperties) Make sure that constructor always assigns an empty string.

Co-authored-by: magnesj <magnesj@users.noreply.github.com>
Co-authored-by: Kristian Bendiksen <kristian.bendiksen@gmail.com>

ApplicationLibCode/Commands/RicImportFormationNamesFeature.cpp

@@ -89,7 +89,9 @@ RimFormationNames* RicImportFormationNamesFeature::importFormationFiles( const Q
         }
     }
 
-    return formationNames.back();
+    if ( !formationNames.empty() ) return formationNames.back();
+
+    return nullptr;
 }
 
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