Update documentation assets

Author: Bombardier-C-Kram

docs/documentation-assets

@@ -4,7 +4,6 @@ repo_name: Dyalog/OpenAPI
 copyright: Made with <a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener"><strong>Material for MkDocs</strong></a><br/>Copyright &copy; 1982-$CURRENT_YEAR <strong><a href="https://dyalog.com" target="_blank" rel="noopener">Dyalog Limited</a></strong> (<a href="#" class="copy" onclick="navigator.clipboard.writeText(innerText);return false" title="Click to copy!">$BUILD_DATE $GIT_INFO</a>).<br/>Except where otherwise noted, content on this site is licensed under a <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" rel="noopener"><strong>Creative Commons Attribution 4.0 International</strong></a> licence.
 
 theme:
-  favicon: 'documentation-assets/images/favicon-32.png'
   logo: documentation-assets/images/dyalog-logo_white.svg
   features:
     - navigation.instant
@@ -15,6 +14,7 @@ theme:
   name: material
   font:
       text: Be Vietnam Pro
+  custom_dir: docs/documentation-assets/overrides
 extra_css:
   - documentation-assets/css/main.css
   - documentation-assets/css/extra.css