PR Summary

This PR simply tries to make the examples added in #10306 a bit more consistent with the current trend of promoting the object-oriented API rather than the Pyplot one. I was planning to suggest the small changes in the original thread but the latter got merged while I was writing my post 🐑...

Being there, this PR also slightly increase the title padding in title_xlabel_top.py, to make room for the tick labels and prevent a not very nice-looking overlap. Please note that this change could (should) be removed if in the future a feature like #9498 was going to be introduced in Matplotlib.

Some questions that may still be open:

• Should we merge the one examples into a single one? (I do not remember where we are about having very short and simple examples vs more complex/comprehensive ones)
• If we prefer keeping two different files, should we make the names a bit more consistent? (e.g. tick_label_right.py <- tick_ylabel_right.py)

PR Checklist

• Code is PEP 8 compliant: hopefully
• Documentation is sphinx and numpydoc compliant: CI will judge