Fixed import of render mermaid & render math methods

app/assets/javascripts/main.js

@@ -69,8 +69,6 @@ import './project_import';
 import './projects_dropdown';
 import './projects_list';
 import './syntax_highlight';
-import './render_math';
-import './render_mermaid';
 import './render_gfm';
 import './right_sidebar';
 import './search';

app/assets/javascripts/render_gfm.js

-/* eslint-disable func-names, space-before-function-paren, consistent-return, no-var, no-else-return, prefer-arrow-callback, max-len */
+import './render_math';
+import './render_mermaid';
 
 // Render Gitlab flavoured Markdown
 //
 // Delegates to syntax highlight and render math & mermaid diagrams.
 //
-(function() {
-  $.fn.renderGFM = function() {
+$.fn.renderGFM = function renderGFM() {
   this.find('.js-syntax-highlight').syntaxHighlight();
   this.find('.js-render-math').renderMath();
   this.find('.js-render-mermaid').renderMermaid();
   return this;
-  };
+};
 
-  $(() => $('body').renderGFM());
-}).call(window);
+$(() => $('body').renderGFM());