[pyramid] Get rid of a bare "except" in UpdateLoginTimeAuthenticationPolicy Also refactor a bit the method to restrict the try/except block to the code for which we actually want to catch an exception (i.e. the cnx.execute() + cnx.commit()).

version=3
opts=uversionmangle=s/(rc|a|b|c)/~$1/ \
https://pypi.debian.net/cubicweb/cubicweb-(.+)\.(?:zip|tgz|tbz|txz|(?:tar\.(?:gz|bz2|xz)))