Update to accept resource ResourceBase rather than Resource

Author: timsavage

src/odin/filtering.py

@@ -8,9 +8,7 @@
 
 
 class FilterAtom(abc.ABC):
-    """
-    Base filter statement
-    """
+    """Base filter statement"""
 
     __slots__ = ()
 

src/odin/resources.py

@@ -171,7 +171,9 @@ def composite_fields(self) -> Sequence[Field]:
         """All composite fields."""
         # Not the nicest solution but is a fairly safe way of detecting a composite field.
         return tuple(
-            f for f in self.fields if (hasattr(f, "of") and issubclass(f.of, Resource))
+            f
+            for f in self.fields
+            if (hasattr(f, "of") and issubclass(f.of, ResourceBase))
         )
 
     @cached_property