[OMCPath] differentiate between Windows and Posix for OMCPathCompatibility

Author: syntron

OMPython/OMCSession.py

@@ -420,7 +420,12 @@ def size(self) -> int:
         stacklevel=1,
     )
 
-    class OMCPathCompatibility(pathlib.Path):
+    if os.name == 'nt':
+        pathdef = pathlib.WindowsPath
+    else:
+        pathdef = pathlib.PosixPath
+
+    class OMCPathCompatibility(pathdef):
 
         def size(self) -> int:
             return self.stat().st_size