Fix link scope (pydata#1931)

Typically, one does not include articles in the link.

docs/index.md

@@ -29,7 +29,7 @@ A clean, Bootstrap-based Sphinx theme by and for [the PyData community](https://
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 ```{seealso}
-If you are looking for a Sphinx theme that puts all of its sub-pages in the sidebar, the [Sphinx Book Theme](https://sphinx-book-theme.readthedocs.io/) has a similar look and feel, and [Furo](https://pradyunsg.me/furo/quickstart/) is another excellent choice. You can also see [the Sphinx Themes Gallery](https://sphinx-themes.org) for more ideas.
+If you are looking for a Sphinx theme that puts all of its sub-pages in the sidebar, the [Sphinx Book Theme](https://sphinx-book-theme.readthedocs.io/) has a similar look and feel, and [Furo](https://pradyunsg.me/furo/quickstart/) is another excellent choice. You can also see the [Sphinx Themes Gallery](https://sphinx-themes.org) for more ideas.
 ```
 
 ## User Guide