fixup! feature: add support for GLFM math blocks

Author: stephanlachnit

layouts/_default/_markup/render-codeblock-math.html

@@ -1,3 +1,3 @@
-<p>```math
+<p>$$
 {{ .Inner | safeHTML }}
-```</p>
+$$</p>

userguide/content/en/docs/Adding content/diagrams-and-formulae/index.md

@@ -93,10 +93,6 @@ errorColor = "#CD5C5C"
   left = "\\["
   right = '\\]'
   display = true
-[[params.katex.options.delimiters]]
-  left = "```math"
-  right = '```'
-  display = true
 ```
 
 For a complete list of options and their detailed description, have a look at the documentation of \\({\KaTeX}'s\\) [Rendering API options](https://katex.org/docs/autorender.html#api) and of \\({\KaTeX}'s\\) [configuration options](https://katex.org/docs/options.html).