Use isinstance instead of type

Author: mgmarino

pandas/core/internals/concat.py

@@ -443,7 +443,7 @@ def _is_uniform_join_units(join_units: List[JoinUnit]) -> bool:
     #  cannot necessarily join
     return (
         # all blocks need to have the same type
-        all(type(ju.block) is type(join_units[0].block) for ju in join_units)
+        all(isinstance(ju.block, join_units[0].block) for ju in join_units)
         and  # noqa
         # no blocks that would get missing values (can lead to type upcasts)
         # unless we're an extension dtype.