fixing windows test errors

tests/test_entry_points.py

@@ -3,15 +3,18 @@
 import importlib.util
 import sys
 from pathlib import Path
+import os
 
 def test_entry_points():
     """Testing if the entry points are loading right"""
 
     entry_points = list(pybamm_cookiecutter.parameter_sets)
     parameter_sets = Path("src/pybamm_cookiecutter/parameters/input/").glob("*.py")
+    if os.name == 'posix':
     # Making a list Parameter sets in the parameters/input directory
-    parameter_sets = [str(x).split('/')[-1].split('.py')[0] for x in parameter_sets]
-
+        parameter_sets = [str(x).split('/')[-1].split('.py')[0] for x in parameter_sets]
+    elif os.name == 'nt':
+        parameter_sets = [str(x).split('//')[-1].split('.py')[0] for x in parameter_sets]
     assert parameter_sets == entry_points, "Entry points missing either in pyproject.toml or in the input directory"
 
 def test_entry_point_load():