Panel is too small on HiDPI + X11

[danirabbit]

What Happened?

The panel is smaller than it should be when using HiDPI and X11 together

Steps to Reproduce

1. Use a HiDPI X11 session without enabling experimental fractional scaling
2. See that the panel is too small

Expected Behavior

Panel is the correct size in all sessions. Probably should have a special case handler for X11 session in src/Services/DisplayConfig.vala

OS Version

8.x (Early Access)

Software Version

Compiled from git

Log Output

No response

Hardware Info

No response