GHSA-g3cp-pq72-hjpv

### Summary
All system messages in menu headings using the Menu.mustache template are inserted as raw HTML, allowing anybody who can edit those messages to insert arbitrary HTML into the DOM.

### Details
The system messages for menu headings are inserted unescaped into raw HTML:
https://github.com/StarCitizenTools/mediawiki-skins-Citizen/blob/072e4365e9084e4b153eac62d3666566c06f5a49/templates/Menu.mustache#L8-L10

### PoC
1. Go to any article using citizen with the `uselang` parameter set to `x-xss`
2. A large number of alerts will be shown for various messages, e.g.:

On the main page of my test wiki, the following messages were shown: `navigation`, `notifications`, `user-interface-preferences`, `personaltools`, `variants`, `views`, `associated-pages`, `cactions` and `toolbox`.

### Impact
This impacts wikis where a group has the `editinterface` but not the `editsitejs` user right.