Content-Type in response header is incorrect on resources in Wiki page
Summary
After migration from 11.4.5 to 11.5.0-ee (cb71fca3) the content-type of files stored in the wiki project always return text/plain regardless of the extension/mime
Steps to reproduce
Upload an html page, css and js into the wiki project and access it via the browser.
Example Project
https://gitlab.com/LeandroPT/testwiki.git
Go to the wiki and press the link available
using a tool like "Requestly" and changing the response Header Content Type to the correct type the page renders properly
What is the current bug behavior?
Content-Type response header for wiki raw file content is incorrect for html, css, js files.
The previous version had the problem described in #26390 (moved) that is no longer an issue in this release.
What is the expected correct behavior?
The correct Content-Type header according to the extension
Output of checks
This bug happens on GitLab.com
Edited by Leandro Teixeira