packaging: fixed spec file
packaging: fixed spec file

There were several issues for the spec file (e.g. ruby 2.5 -> 2.6 transition,
minor issues around declaring packaged files, etc.). This commit addresses all
these issues.

Signed-off-by: Miquel Sabaté Solà <b4d70704b9e7df580cab34510621dbd0aacb2dfd@suse.com>

mssola/Portus,SUSE/Portus,SUSE/Portus,SUSE/Portus,SUSE/Portus,mssola/Portus,mssola/Portus,mssola/Portus