DOC: Fix swaplevel docstring (#44740)

Author: TheNeuralBit

pandas/core/frame.py

@@ -6790,7 +6790,8 @@ def nsmallest(self, n: int, columns: IndexLabel, keep: str = "first") -> DataFra
             'columns' for column-wise."""
         ),
         examples=dedent(
-            """Examples
+            """\
+        Examples
         --------
         >>> df = pd.DataFrame(
         ...     {"Grade": ["A", "B", "A", "C"]},

pandas/core/series.py

@@ -3897,7 +3897,8 @@ def nsmallest(self, n: int = 5, keep: str = "first") -> Series:
             Whether to copy underlying data."""
         ),
         examples=dedent(
-            """Examples
+            """\
+        Examples
         --------
         >>> s = pd.Series(
         ...     ["A", "B", "A", "C"],