Fixed crash when package test resources overlap sources

Fixed a generation crash when a local Swift package test target uses resources: [.copy(“.”)]. Starting in 4.182.0, preserving those test targets caused Tuist to treat the copied resource folder and the test source files as conflicting project elements, which produced the error about adding a file to a missing build phase. Tuist now allows folder references to coexist with logical source groups at the same path, so projects with package test resources generate successfully again.