Issue with multi-backend-testing

[MikaelMayer]

Currently, running the following command has a problematic side-effect

DAFNY_INTEGRATION_TESTS_IN_PROCESS=true
DAFNY_INTEGRATION_TESTS_MODE=only-multi-backend
DAFNY_INTEGRATION_TESTS_ONLY_COMPILERS=dfy
DAFNY_INTEGRATION_TESTS_ROOT_DIR=..../dafny/Source/IntegrationTests
DAFNY_INTEGRATION_TESTS_UPDATE_EXPECT_FILE=true
dotnet test Source/IntegrationTests/IntegrationTests.csproj

Indeed, it starts creating .dfy.dfy.check files for EVERY file because none of them pass the ResolvedDesugaredExecutableDafny backend by throwing FeatureNotImplementedException(Feature.RunAllText), which is just a placeholder for "this backend is exected to fail here no need to report it".
These files all contain the following:

// CHECK-L: (0,-1): Error: Feature not supported for this compilation target: The /runAllTests option

It's for every file because this gets called for every file
_out14 = D2DPrettyPrinter.__default.PrettyPrint(p);
which launches the following:
Microsoft.Dafny.Compilers.WrapException.Throw();
in any case.

While is is technically correct, at the moment there is not a single integration test file that will not emit that check file, and these check files are useless for now.
Our CI does not care as it's not set up to generate files. However, locally, if we are set up to generate those files, they will start appearing and it's a bit problematic.

The reason why ResolvedDesugaredExecutableDafny is marked as stable is to be able to catch any other exception than the one mentioned above.
But now I realize it's an issue. Perhaps I should just deactivate the emitting of check files for that particular compiler, what do you think @robin-aws ?