Updating Callouts to resolve following defects found in testing.

- Icon does not start at top of the page with text.

Markdoc changes the order that CSS classes get applied to child elements compared to preexisting MDX approach so some changes are required to make sure the child elements style correctly.
- Child text does not receive colors.text style for some element types.
- Child text does not receive text-sm class in some cases.

The function applyTextStyles addresses this.

docs/next/styles/globals.css

@@ -617,4 +617,4 @@ td {
 
 .admonition > :last-child {
   margin-bottom: 0;
-}
+}