Unable to publish a template if it contains a broken link

Issue Summary

Users are not able to publish an existing page template if it contains a broken page link.

Steps to Reproduce

1. Create a test page on confluence and copy the link
2. Go to Global Templates and Blueprints page - https://yoursitename.atlassian.net/wiki/pages/templates2/listglobaltemplates.action
3. Click add global page template.
4. Add a title and paste the link you copied on step 1.
5. Save the template.
6. Now, delete the test page and purge it from the space thrash.
7. Then go back to the global page template and click edit.
8. After that, click save

Expected Results

The page template saves without error.

Actual Results

User sees the below error when clicking save:

There was an error processing the request.

Workaround

Remove the broken link and click Save.