Outdated Vue testing API post vue migration

[gerteck]

Please confirm that you have searched existing issues in the repo

Yes, I have searched the existing issues

Any related issues?

No response

Tell us about your environment

Win 11

MarkBind version

5.6.0

Describe the bug and the steps to reproduce it

Some small errors in the latest Vue component tests that were developed across the Vue Migration.

https://github.com/MarkBind/markbind/actions/runs/14427236057/job/40457716727#step:8:170

This is due to the difference in Vue testing API from Vue 2 to Vue 3.

Expected behavior

No response

Anything else?

Will push PR to update it.