MDL-84970 editor_tiny: Use the langpack name for Moodle language

lib/editor/tiny/amd/src/editor.js

@@ -29,6 +29,7 @@ import * as Options from './options';
 import {addToolbarButton, addToolbarButtons, addToolbarSection,
     removeToolbarButton, removeSubmenuItem, updateEditorState} from './utils';
 import {addMathMLSupport, addSVGSupport} from './content';
+import Config from 'core/config';
 
 /**
  * Storage for the TinyMCE instances on the page.
@@ -155,7 +156,7 @@ export const setupForElementId = ({elementId, options}) => {
 const initialisePage = async() => {
     const lang = document.querySelector('html').lang;
 
-    const [tinyMCE, langData] = await Promise.all([getTinyMCE(), fetchLanguage(lang)]);
+    const [tinyMCE, langData] = await Promise.all([getTinyMCE(), fetchLanguage(Config.language)]);
     tinyMCE.addI18n(lang, langData);
 };
 initialisePage();