CON-1786 | Recent Wiki Activity for logged in user on Venus

https://wikia-inc.atlassian.net/browse/CON-1786

Don't merge without config: https://github.com/Wikia/config/pull/720
@Warkot I can't find any usage of this color so far, that's why I suggest not extracting it to shared file. Let's be agile and extract it when we find next use-case.
Background color for infoboxes is set by users so I suspect it's coincidence on mockups that those color matches.