Fix mypy issues

src/rechunk_data/__init__.pyi

 import argparse
 import os
 from pathlib import Path
-from typing import Any, Dict, Generator, Optional, Tuple
+from typing import Any, Dict, Generator, List, Optional, Tuple
 
 import xarray as xr
 
@@ -16,4 +16,6 @@ def rechunk_netcdf_file(
     output_path: Optional[os.PathLike] = ...,
     engine: str = ...,
 ) -> None: ...
-def cli() -> None: ...
+def cli(
+    argv: Optional[List[str]] = ...,
+) -> None: ...

src/rechunk_data/tests/test_rechunk_netcdf.py

@@ -20,7 +20,7 @@ def test_rechunk_data_dir_with_overwrite(data_dir: Path) -> None:
 def test_rechunk_data_dir_without_overwrite(data_dir: Path) -> None:
     """Testing the creation of new datafiles from a folder."""
     with TemporaryDirectory() as temp_dir:
-        rechunk_netcdf_file(data_dir, temp_dir)
+        rechunk_netcdf_file(data_dir, Path(temp_dir))
         new_files = sorted(f.relative_to(temp_dir) for f in Path(temp_dir).rglob(".nc"))
     old_files = sorted(f.relative_to(data_dir) for f in data_dir.rglob(".nc"))
     assert new_files == old_files
@@ -34,7 +34,7 @@ def test_rechunk_single_data_file(data_file: Path) -> None:
         rechunk_netcdf_file(data_file)
         assert a_time < float(data_file.stat().st_atime)
         with NamedTemporaryFile(suffix=".nc") as temp_file:
-            rechunk_netcdf_file(data_file, temp_file.name)
+            rechunk_netcdf_file(data_file, Path(temp_file.name))
             assert Path(temp_file.name).exists()