From PR https://github.com/ManageIQ/manageiq/pull/12499:
This change makes our Yes and No labels in patternfly styled check box inputs translatable.
We merged latest translations for 5.8 only recently, which is why you
see the problem. The translations should be available in next 5.8. build.
yes/no and on/off labels are translated in checkbox tag.
Verified Version: 126.96.36.199-rc1.20170425180304_4f35996
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.