Closes #398

We have a framework that has a build condition SWIFT_ACTIVE_COMPILATION_CONDITIONS = APPEXTENSION; And based on that condition, we are importing the following libraries.

#if APPEXTENSION
import CustomAppExtension
#else
import Custom
#endif

The problem we are facing is that the generated mocks do not have this #if statement. They import both libraries (which causes a build fail) like below:

import CustomAppExtension
import Custom

Instead, we would require the imports to happen as in the original file:

#if APPEXTENSION
import CustomAppExtension
#else
import Custom
#endif

Would it be possible to update Cuckoo to recognize that #if block?

My solution is to check the possibility to import framework:

#if canImport(CustomAppExtension)
import CustomAppExtension
#endif

#if canImport(Custom)
import Custom
#endif

This fix works when the single framework is embedded into the target.