fixing the path find issue with wrong slash direction. This was causi…

…ng errors when deleting sub-projects with deeper level (2+)

tik_manager4/objects/subproject.py

@@ -464,7 +464,7 @@ def _remove_sub_project(self, uid=None, path=None):
             if state != 1:
                 return -1
 
-        parent_path = str(Path(kill_sub.path).parent) or ""
+        parent_path = (Path(kill_sub.path).parent).as_posix() or ""
         parent_sub = self.find_sub_by_path(parent_path)
         del parent_sub.subs[kill_sub.name]