Merged requested to merge clemenci/Gaudi:replace-statuscodesvc-with-nodiscard into master
this allow spotting unchecked
StatusCodes at compile time instead of at run time.
I also fixed O(250) unchecked
StatusCodes in Gaudi (in ~60 files), using the script $587.
With this we can remove
StatusCodeSvc with the overhead it implies (@graven noted that removing
~StatusCode we will also save some time because the return will be done via registers).
This also remove the
WARN_UNUSED macro introduced with !386 (merged) (redundant).