Web IDE markdown visualisator have issue with image path

Summary

Web IDE markdown visualisator have issue with image path, the path is not relative but absolute.

Steps to reproduce

1. have a repository with this hieracrchiy:

/doc/mydoc.md /doc/images/myimage.png

2. into mydoc.md have

3. go to Web IDE > open /doc/mydoc.md > click on preview markdown tab

Result:=> the image is not visible

the link to the image is not relative : https://gitlab.server.com/user/repo/master/images/myimage.png

The visualisation work fine we open file into gitlab as:

https://gitlab.server.com/user/repo/blob/master/doc/mydoc.md