[Bug] Not able to cimort loop from pyx file

when trying to import uvloop.Loop from a pyx file, using
```python
from uvloop.loop cimport Loop
```

gives this error, seemingly missing header file.

```bash
 fatal error: includes/compat.h: No such file or directory
 1243 | #include "includes/compat.h"
```

```bash
Python 3.12.9
Distributor ID: Ubuntu
Description:    Ubuntu 20.04.6 LTS
Release:        20.04
Codename:       focal
```
