XCTest Swift, since XCode 12.5 not usable, error: cannot find 'XCTAssertEqual' in scope


I have some Sift code that I build and test with CMake
Since XCode 12.5, there has been an issue that the compilation of my XCTest does not work anymore.

The build stops with error: cannot find 'XCTAssertEqual' in scope

There is a notice at the end of the release notes of XCode 12.5 about some test removemnt.

In XCode, people can set ENABLE_TESTING_SEARCH_PATHS , and that shall fix the problem.
But I can not figure out how to do that in CMake,

Example project can be found here, as soon as I add the test sub folder, I get the error

Any way to get testing into my code with CMake ?