docs: fix broken relative page links (#1106)

In touching up the migration guide, I noticed that many of our documentation site links are broken! For example, on the homepage, this link:

<img width="782" alt="screenshot of homepage; code snippet is in next block" src="https://user-images.githubusercontent.com/14893287/210462690-31aa7bf5-dd79-4e8f-a3c5-1213e73771c4.png">

which has the following href

```code
<a href="/just-the-docs/just-the-docs/CHANGELOG/">the CHANGELOG</a>
```

duplicates the `baseurl` twice. There are 14 such broken links across the site. Each link duplicates the `baseurl` and `link` tags, which has since been resolved with links being relative by default (there's a set of PRs that document this - I can't find the exact paper trail right now).

To resolve this, I:

- find and replace site-wide `{{ site.baseurl }}{% link` with `{% link`
- tested each link, which now works properly locally *and* on the deploy preview

I'm surprised we didn't catch this earlier! I also could be missing something else, in which case feedback on this PR is certainly welcome.

docs/ui-components/buttons.md

@@ -56,7 +56,7 @@ GitHub Flavored Markdown does not support the `button` element, so you'll have t
 
 ### Button size
 
-Wrap the button in a container that uses the [font-size utility classes]({{ site.baseurl }}{% link docs/utilities/typography.md %}) to scale buttons:
+Wrap the button in a container that uses the [font-size utility classes]({% link docs/utilities/typography.md %}) to scale buttons:
 
 <div class="code-example" markdown="1">
 <span class="fs-6">
@@ -79,7 +79,7 @@ Wrap the button in a container that uses the [font-size utility classes]({{ site
 
 ### Spacing between buttons
 
-Use the [margin utility classes]({{ site.baseurl }}{% link docs/utilities/layout.md %}#spacing) to add spacing between two buttons in the same block.
+Use the [margin utility classes]({% link docs/utilities/layout.md %}#spacing) to add spacing between two buttons in the same block.
 
 <div class="code-example" markdown="1">
 [Button with space](http://example.com/){: .btn .btn-purple .mr-2 }

docs/ui-components/callouts.md

@@ -7,14 +7,14 @@ nav_order: 7
 
 # Callouts
 
-Markdown does not include support for callouts. However, you can style text as a callout using a Markdown extension supported by kramdown: [*block IALs*](https://kramdown.gettalong.org/quickref.html#block-attributes). 
+Markdown does not include support for callouts. However, you can style text as a callout using a Markdown extension supported by kramdown: [*block IALs*](https://kramdown.gettalong.org/quickref.html#block-attributes).
 
 Common kinds of callouts include `highlight`, `important`, `new`, `note`, and `warning`.
 
 {: .warning }
 These callout names are *not* pre-defined by the theme: you need to define your own names.
 
-When you have [configured]({{ site.baseurl }}{% link docs/configuration.md %}#callouts) the  `color` and (optional) `title` for a callout, you can apply it to a paragraph, or to a block quote with several paragraphs, as illustrated below.[^postfix]
+When you have [configured]({% link docs/configuration.md %}#callouts) the  `color` and (optional) `title` for a callout, you can apply it to a paragraph, or to a block quote with several paragraphs, as illustrated below.[^postfix]
 
 [^postfix]:
     You can put the callout markup either before or after its content.

docs/ui-components/typography.md

@@ -111,4 +111,4 @@ Text can be **bold**, _italic_, or ~~strikethrough~~.
 
 There are a number of specific typographic CSS classes that allow you to override default styling for font size, font weight, line height, and capitalization.
 
-[View typography utilities]({{ site.baseurl }}{% link docs/utilities/typography.md %}){: .btn .btn-outline }
+[View typography utilities]({% link docs/utilities/typography.md %}){: .btn .btn-outline }