HTML tags displayed when changing base URL

[fj-sanchez]

Description of problem

When login for the first time and going to settings to change the base URL, a pop-up message is displayed at the top. In this message some HTML tags are displayed instead of being interpreted.

Version or commit hash (if applicable)

latest docker (v6.9)

Steps to Reproduce

1. Run latest docker images
2. Run the script to initialise the database
3. Run the command to create a superuser
4. Login with the superuser account
5. Click on change base URL in the pop-up message

Actual results

A pop-up message at the top can be read with this text:

Base URL is not configured! See <a href="https://kiwitcms.readthedocs.io/en/latest/admin.html#configure-kiwi-s-base-url">documentation</a> and <a href="/admin/sites/site/1/change/">change it</a>

Expected results

The same message but with an actual link instead of the HTML tags.

Additional info (Python traceback, logs, etc.)