Apps page broken again in 5.2.0

[Paul Staroch]

Describe the bug
After updating to Rocket.Chat 5.2.0, the problem from #193 is back: The apps page is not dark anymore.

To Reproduce
Steps to reproduce the behavior:

1. Update to Rocket.Chat 5.2.0.
2. Open the apps page (now labelled "Marketplace").

Expected behavior

Actual behavior