global: deprecation warning update
global: deprecation warning update

* Updates the RuntimeWarning to DeprecationWarning when
  rendering jinja2 templates with bytestrings.

Co-authored-by: Jiri Kuncar <2bdffcb416fed3002465740d19a053a39918cbe5@cern.ch>
Signed-off-by: Jan Aage Lavik <8d55e006a1b29770f275a5c59a7341f17f8e69d5@cern.ch>

tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio,tiborsimko/invenio