Remove: (layouts/partials/head.html) Empty file

In accordance with the recommendations in
<https://gohugo.io/content-management/mathematics>, the HTML HEAD
content goes in "baseof.html" rather than here, and after removing the
old implementation, this file is empty.

Author: alphapapa

layouts/_default/baseof.html

@@ -8,9 +8,6 @@
     <!-- Render theme css -->
     {{ partial "css.html" . -}}
 
-    <!-- Render custom header -->
-    {{ partial "head.html" . -}}
-
     <!-- Refer: https://regisphilibert.com/blog/2018/08/hugo-multilingual-part-1-managing-content-translation/ -->
     {{ if .IsTranslated }}
       {{ range .Translations }}