Update conf.py (pydata#8390)

Author: Illviljan

doc/conf.py

@@ -237,7 +237,6 @@
     use_repository_button=True,
     use_issues_button=True,
     home_page_in_toc=False,
-    navigation_with_keys=False,
     extra_footer="""<p>Xarray is a fiscally sponsored project of <a href="https://numfocus.org">NumFOCUS</a>,
     a nonprofit dedicated to supporting the open-source scientific computing community.<br>
     Theme by the <a href="https://ebp.jupyterbook.org">Executable Book Project</a></p>""",