Backport PR matplotlib#24399: Fix docstring of Figure.subfigures.

Author: oscargus

lib/matplotlib/figure.py

@@ -1520,7 +1520,7 @@ def subfigures(self, nrows=1, ncols=1, squeeze=True,
                    width_ratios=None, height_ratios=None,
                    **kwargs):
         """
-        Add a subfigure to this figure or subfigure.
+        Add a set of subfigures to this figure or subfigure.
 
         A subfigure has the same artist methods as a figure, and is logically
         the same as a figure, but cannot print itself.