MAINT: do not skip nonexistent file when building sdist

The native file is not intended to be added to version control, thus
it should never have be present in the dist archive prepared by Meson.
With it moved to the build directory there is no risk of it ever being
present.

mesonpy/__init__.py

@@ -1036,10 +1036,6 @@ def sdist(self, directory: Path) -> pathlib.Path:
 
         with tarfile.open(meson_dist_path, 'r:gz') as meson_dist, mesonpy._util.create_targz(sdist) as (tar, mtime):
             for member in meson_dist.getmembers():
-                # skip the generated meson native file
-                if member.name == f'{meson_dist_name}/.mesonpy-native-file.ini':
-                    continue
-
                 # calculate the file path in the source directory
                 assert member.name, member.name
                 member_parts = member.name.split('/')