Merged requested to merge nielsdg/fix-snprintf-truncation-warning into master
When enabling fatal warnings (like in our CI), the
-Werror=format-truncation= flag is complaining about us using
snprintf() in a way that can theoretically truncate its arguments,
even though this will not happen in practice, unless people are still
running gnome-keyring in the year 100000.
Solve the warning by doing a dumb check that aborts if
returns an error