`/cygdrive/d/HOME/.emacs.d/test/task-3.3.0/Cargo.toml` does not exist

I encountered a similar problem on Cygwin, despite the fact that `Cargo.toml` does exist:

```
-- Using Corrosion as a subdirectory
error: manifest path `/cygdrive/d/HOME/.emacs.d/test/task-3.3.0/Cargo.toml` does not exist
CMake Error at src/taskchampion-cpp/corrosion/cmake/CorrosionGenerator.cmake:26 (execute_process):
execute_process failed command indexes:

1: "Child return code: 101"

Call Stack (most recent call first):
src/taskchampion-cpp/corrosion/cmake/CorrosionGenerator.cmake:227 (_cargo_metadata)
src/taskchampion-cpp/corrosion/cmake/Corrosion.cmake:1113 (_generator_add_cargo_targets)
src/taskchampion-cpp/CMakeLists.txt:19 (corrosion_import_crate)
```

_Originally posted by @AnabasisXu in https://github.com/GothenburgBitFactory/taskwarrior/issues/3378#issuecomment-2586337241_