Remove Scatter and Hexbin from Series plot documentation (#39000)

Author: 1nF0rmed

pandas/plotting/_core.py

@@ -630,8 +630,8 @@ class PlotAccessor(PandasObject):
         - 'density' : same as 'kde'
         - 'area' : area plot
         - 'pie' : pie plot
-        - 'scatter' : scatter plot
-        - 'hexbin' : hexbin plot.
+        - 'scatter' : scatter plot (DataFrame only)
+        - 'hexbin' : hexbin plot (DataFrame only)
     ax : matplotlib axes object, default None
         An axes of the current figure.
     subplots : bool, default False