[pkg] Fix doc-base section
As pointed by Lintian, the “Apps” section is only used in menu,
not in doc-base. We can just remove it.
extend-diff-ignore = "^(__pkginfo__\.py$|doc/_themes/cubicweb/static/(logo-cubicweb-small\.svg|cubicweb\.ico|logo-cubicweb\.svg)$|cubicweb/(sobjects/test/data/(cubicweb_comment|cubicweb_card)|server/test/data-migractions/(migratedapp/)?(cubicweb_comment|cubicweb_localperms|cubicweb_basket|cubicweb_tag|cubicweb_card|cubicweb_file)|test/data-rewrite/(cubicweb_localperms|cubicweb_card))$|cubicweb\.spec$|setup\.cfg$|cubicweb/misc/cwfs)"