Revert "Add workaround for theme versions that don't support mode switcher."

This reverts commit 26caf95.

Author: rossbar

doc/conf.py

@@ -83,17 +83,8 @@
 html_theme_options = {
     "github_url": "https://github.com/numpy/numpydoc",
     "show_prev_next": False,
-    "navbar_end": ["search-field.html", "navbar-icon-links.html"],
+    "navbar_end": ["theme-switcher", "search-field.html", "navbar-icon-links.html"],
 }
-# Add version switcher for versions of pydata_sphinx_theme that support it
-import packaging
-import pydata_sphinx_theme
-
-if packaging.version.parse(pydata_sphinx_theme.__version__) >= packaging.version.parse(
-    "0.9.0"
-):
-    html_theme_options["navbar_end"].insert(0, "theme-switcher")
-
 html_sidebars = {
     "**": [],
 }