Add workaround for broken importlib.resources when an editable sentin…

…el is present.

Closes #318

importlib_resources/future/adapters.py

@@ -23,6 +23,13 @@ def wrapper(*args, **kwargs):
         except NotADirectoryError:
             # MultiplexedPath may fail on zip subdirectory
             return
+        except ValueError as exc:
+            # NamespaceReader in stdlib may fail for editable installs
+            # (python/importlib_resources#311, python/importlib_resources#318)
+            # Remove after bugfix applied to Python 3.13.
+            if "not enough values to unpack" not in str(exc):
+                raise
+            return
         # Python 3.10+
         mod_name = reader.__class__.__module__
         if mod_name.startswith('importlib.') and mod_name.endswith('readers'):