Test Case Importer doesn't take into account Custom Fields' Configuration Scheme

Test Case Importer doesn't take into account Custom Fields' Configuration Scheme.

The Test Case Importer, when importing a Custom Field with Options (Single/Multi Select, Cascading Multiselect, etc...) we only take into account the Options of the Default Scheme Configuration, and not any other that may exist and be applicable.
 

Steps to Reproduce:

1. Create a new Single Select Custom Field
2. Add it to a screen in an existing Project (e.g. Calculator)
3. Add 3 options to the Default Scheme Configuration: A, B, C
4. Create a new Scheme for the previous project with the following options: AA, BB, CC
   1. At the end, you should have a configuration similar to the attached image
5. Try to import the attached CSV file to the previous project
6. At the end of the import, it will display an error saying that the Custom Field couldn't be mapped, however, it should have the value 'AA'