chore: remove unused plugin and lerna package (#41258)

client/gatsby-config.js

@@ -56,37 +56,7 @@ module.exports = {
       }
     },
     {
-      resolve: 'gatsby-transformer-remark',
-      options: {
-        plugins: [
-          'gatsby-remark-fcc-forum-emoji',
-          {
-            resolve: 'gatsby-remark-prismjs',
-            options: {
-              // Class prefix for <pre> tags containing syntax highlighting;
-              // defaults to 'language-' (eg <pre class="language-js">).
-              // If your site loads Prism into the browser at runtime,
-              // (eg for use with libraries like react-live),
-              // you may use this to prevent Prism from re-processing syntax.
-              // This is an uncommon use-case though;
-              // If you're unsure, it's best to use the default value.
-              classPrefix: 'language-',
-              // This is used to allow setting a language for inline code
-              // (i.e. single backticks) by creating a separator.
-              // This separator is a string and will do no white-space
-              // stripping.
-              // A suggested value for English speakers is the non-ascii
-              // character '›'.
-              inlineCodeMarker: null,
-              // This lets you set up language aliases.  For example,
-              // setting this to '{ sh: "bash" }' will let you use
-              // the language "sh" which will highlight using the
-              // bash highlighter.
-              aliases: {}
-            }
-          }
-        ]
-      }
+      resolve: 'gatsby-transformer-remark'
     },
     {
       resolve: 'gatsby-remark-node-identity',