fix(shareDialog): 修复分享链接的文件后缀为html

将admin.htm修正为admin.html，匹配正确的路由文件后缀

src/components/pptEasyClass/shareDialog.vue

@@ -88,7 +88,7 @@ export default {
       else if (this.lang.lang === 'en') {
         url = 'https://cloud.cocorobo.com'
       }
-      this.form.url = `${url}/admin.htm?orgnum=${this.courseId}&classcode=${this.classId}`;
+      this.form.url = `${url}/admin.html?orgnum=${this.courseId}&classcode=${this.classId}`;
       // this.getData();
     },
     close() {