REF: share IntegerArray/FloatingArray extension tests (#54331)

* REF: move bits of IntegerArray/FloatingArray tests to masked_shared

* REF: combine Floating/Integer tests

* REF: move masked_shared back into test_integer

* REF: test_integer.py -> test_masked_numeric.py

* REF: change silent early return to pytest.skip

Author: jbrockmendel

pandas/tests/extension/masked_shared.py

@@ -382,7 +382,7 @@ def check_reduce_frame(self, ser: pd.Series, op_name: str, skipna: bool):
 
         if op_name in ["count", "kurt", "sem"]:
             assert not hasattr(arr, op_name)
-            return
+            pytest.skip(f"{op_name} not an array method")
 
         if op_name in ["mean", "median", "var", "std", "skew"]:
             cmp_dtype = "Float64"