Add issue number (pandas-dev#24313)

Author: alimcmaster1

pandas/tests/frame/test_apply.py

@@ -1140,6 +1140,7 @@ def test_agg_cython_table_raises(self, df, func, expected, axis):
 
     @pytest.mark.parametrize("num_cols", [2, 3, 5])
     def test_frequency_is_original(self, num_cols):
+        # GH 22150
         index = pd.DatetimeIndex(["1950-06-30", "1952-10-24", "1953-05-29"])
         original = index.copy()
         df = DataFrame(1, index=index, columns=range(num_cols))