BUG: Join with a list of a single element behaves as a join with a single element (pandas-dev#57676)

Author: Dacops

pandas/core/frame.py

@@ -10560,6 +10560,9 @@ def join(
         from pandas.core.reshape.concat import concat
         from pandas.core.reshape.merge import merge
 
+        if isinstance(other, list) and len(other) == 1:
+            other = other[0]
+
         if isinstance(other, Series):
             if other.name is None:
                 raise ValueError("Other Series must have a name")