DOC: Remove usage of discouraged layout engine API

Fixes matplotlib#26637

Author: QuLogic

galleries/examples/userdemo/connectionstyle_demo.py

@@ -48,7 +48,7 @@ def demo_con_style(ax, connectionstyle):
 
 for ax in axs.flat:
     ax.set(xlim=(0, 1), ylim=(0, 1.25), xticks=[], yticks=[], aspect=1.25)
-fig.set_constrained_layout_pads(wspace=0, hspace=0, w_pad=0, h_pad=0)
+fig.get_layout_engine().set(wspace=0, hspace=0, w_pad=0, h_pad=0)
 
 plt.show()
 

lib/matplotlib/figure.py

@@ -2466,17 +2466,17 @@ def __init__(self,
               to avoid overlapping axes decorations.  Can handle complex plot
               layouts and colorbars, and is thus recommended.
 
-              See :ref:`constrainedlayout_guide`
-              for examples.
+              See :ref:`constrainedlayout_guide` for examples.
 
             - 'compressed': uses the same algorithm as 'constrained', but
               removes extra space between fixed-aspect-ratio Axes.  Best for
               simple grids of axes.
 
             - 'tight': Use the tight layout mechanism. This is a relatively
               simple algorithm that adjusts the subplot parameters so that
-              decorations do not overlap. See `.set_tight_layout` for
-              further details.
+              decorations do not overlap.
+
+              See :ref:`tight_layout_guide` for examples.
 
             - 'none': Do not use a layout engine.