DOC: Move multiple yaxis example from Spines to Subplots, axes and figures (matplotlib#31765)

The primary aspect here is the multiple Axis feature. Therefore it should live next to the other `twinx()` examples. The spine aspect is only a technical detail need to move the third y-axis. A user would not look for this in the Spines section.

Author: timhoffm

galleries/examples/axisartist/demo_parasite_axes.py

@@ -10,8 +10,8 @@
 `mpl_toolkits.axes_grid1.parasite_axes.ParasiteAxes`.
 
 The standard and recommended approach is to use instead standard Matplotlib
-axes, as shown in the :doc:`/gallery/spines/multiple_yaxis_with_spines`
-example.
+axes, as shown in the
+:doc:`/gallery/subplots_axes_and_figures/multiple_yaxis_with_spines` example.
 
 An alternative approach using `mpl_toolkits.axes_grid1` and
 `mpl_toolkits.axisartist` is shown in the

galleries/examples/axisartist/demo_parasite_axes2.py

@@ -15,8 +15,8 @@
 `mpl_toolkits.axisartist.axislines.Axes`.
 
 The standard and recommended approach is to use instead standard Matplotlib
-axes, as shown in the :doc:`/gallery/spines/multiple_yaxis_with_spines`
-example.
+axes, as shown in the
+:doc:`/gallery/subplots_axes_and_figures/multiple_yaxis_with_spines` example.
 
 An alternative approach using `mpl_toolkits.axes_grid1.parasite_axes.HostAxes`
 and `mpl_toolkits.axes_grid1.parasite_axes.ParasiteAxes` is shown in the

…les/spines/multiple_yaxis_with_spines.py …nd_figures/multiple_yaxis_with_spines.pygalleries/examples/spines/multiple_yaxis_with_spines.py renamed to galleries/examples/subplots_axes_and_figures/multiple_yaxis_with_spines.py galleries/examples/spines/multiple_yaxis_with_spines.py renamed to galleries/examples/subplots_axes_and_figures/multiple_yaxis_with_spines.py

@@ -11,6 +11,8 @@
 `~matplotlib.spines.Spine`\s.  Alternative approaches using non-standard Axes
 are shown in the :doc:`/gallery/axisartist/demo_parasite_axes` and
 :doc:`/gallery/axisartist/demo_parasite_axes2` examples.
+
+.. redirect-from:: /gallery/spines/multiple_yaxis_with_spines
 """
 
 import matplotlib.pyplot as plt
@@ -44,3 +46,6 @@
 ax.legend(handles=[p1, p2, p3])
 
 plt.show()
+
+# %%
+# .. tags:: component: spines