Touch up MyST syntax

Author: stevepiercy

docs/classic-ui/viewlets.md

@@ -74,7 +74,7 @@ To add viewlets to your HTML code, you first need to add them to a viewlet manag
 -   Viewlets can be reordered (limited to reordering within a `viewlet manager`).
 -   Viewlets can be registered and overridden in a theme specific manner using {doc}`/classic-ui/layers`.
 -   Viewlets have `update()` and `render()` methods.
--   Viewlets should honour [zope.contentprovider.interfaces.IContentProvider call contract](https://github.com/zopefoundation/zope.contentprovider/blob/master/src/zope/contentprovider/interfaces.py), documented in [zope.contentprovider](https://zopecontentprovider.readthedocs.io/en/latest/).
+-   Viewlets should honour [`zope.contentprovider.interfaces.IContentProvider` call contract](https://github.com/zopefoundation/zope.contentprovider/blob/master/src/zope/contentprovider/interfaces.py), documented in [`zope.contentprovider`](https://zopecontentprovider.readthedocs.io/en/latest/).
 
 A viewlet can be configured so that it is only available for: