contint: labs slaves +mediawiki::packages::fonts

QA has Jenkins jobs taking screenshots on a wide range of wikis, install
additional fonts on the CI slaves to avoid square boxes in screenshots.

Bug: 69535
Change-Id: I23be62fc8e1f8f32525be0f5a8664b0c862127aa
Merge "contint: labs slaves +mediawiki::packages::fonts" into production