TINY-11908: Fix test

Author: tiny-ben-tran

src/main/ts/Utils.ts

@@ -155,8 +155,8 @@ const mergePlugins = (initPlugins: string | string[] | undefined, inputPlugins?:
 const isNullOrUndefined = (value: any): value is null | undefined =>
   value === null || value === undefined;
 
-const isDisabledOptionSupported = (editor: TinyMCEEditor | null): boolean =>
-  typeof editor?.options.set === 'function' && editor.options.isRegistered('disabled');
+const isDisabledOptionSupported = (editor: TinyMCEEditor): boolean =>
+  typeof editor.options?.set === 'function' && editor.options.isRegistered('disabled');
 
 export {
   bindHandlers,