Backport PR #55050 on branch 2.1.x (Fix docstring of Index.join in ba…

…se.py) (#55217)

Backport PR #55050: Fix docstring of Index.join in base.py

Co-authored-by: Kai Mühlbauer <kmuehlbauer@wradlib.org>
Co-authored-by: Patrick Hoefler <61934744+phofl@users.noreply.github.com>

pandas/core/indexes/base.py

@@ -4586,7 +4586,7 @@ def join(
         -------
         join_index, (left_indexer, right_indexer)
 
-         Examples
+        Examples
         --------
         >>> idx1 = pd.Index([1, 2, 3])
         >>> idx2 = pd.Index([4, 5, 6])