DOC: fix RT03 for pandas.core.groupby.DataFrameGroupBy.hist (#59870)

Author: tuhinsharma121

ci/code_checks.sh

@@ -144,7 +144,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         -i "pandas.core.groupby.DataFrameGroupBy.boxplot PR07,RT03,SA01" \
         -i "pandas.core.groupby.DataFrameGroupBy.get_group RT03,SA01" \
         -i "pandas.core.groupby.DataFrameGroupBy.groups SA01" \
-        -i "pandas.core.groupby.DataFrameGroupBy.hist RT03" \
         -i "pandas.core.groupby.DataFrameGroupBy.indices SA01" \
         -i "pandas.core.groupby.DataFrameGroupBy.nth PR02" \
         -i "pandas.core.groupby.DataFrameGroupBy.nunique SA01" \

pandas/core/groupby/generic.py

@@ -2694,7 +2694,9 @@ def hist(
 
         Returns
         -------
-        matplotlib.Axes or numpy.ndarray of them
+        matplotlib.Axes or numpy.ndarray
+            A ``matplotlib.Axes`` object or an array of ``Axes`` objects, depending on
+            the layout and grouping.
 
         See Also
         --------