DOC: Fix Docstring Validation for pandas.Series.case_when (#58698)

* DOC: add RT03 for pandas.Series.case_when

* DOC: remove RT03 for pandas.Series.case_when

Author: tuhinsharma121

ci/code_checks.sh

@@ -138,7 +138,6 @@ if [[ -z "$CHECK" || "$CHECK" == "docstrings" ]]; then
         -i "pandas.RangeIndex.start SA01" \
         -i "pandas.RangeIndex.step SA01" \
         -i "pandas.RangeIndex.stop SA01" \
-        -i "pandas.Series.case_when RT03" \
         -i "pandas.Series.cat.add_categories PR01,PR02" \
         -i "pandas.Series.cat.as_ordered PR01" \
         -i "pandas.Series.cat.as_unordered PR01" \

pandas/core/series.py

@@ -5324,6 +5324,7 @@ def case_when(
         Returns
         -------
         Series
+            A new Series with values replaced based on the provided conditions.
 
         See Also
         --------