dev-perl/WWW-Bugzilla: EAPI6 + tests

dev-perl/WWW-Bugzilla: EAPI6 + tests

- EAPI6
- Fix DESCRIPTION
- Add very arbitrary minimal tests

Note:
- Builtin tests are well broken for a long time as they rely on
  connecting to the landfill bugzilla server, and then, they only
  support Bugzilla 3.4, which no longer runs on the landfill server.

- The code in question doesn't support working on Bugzilla >3.4

So the tests in place here only confirm it works as far as Perl can
compile it, but doesn't demonstrate the library is actually usable.

A package-mask and tree-removal request are next on the todo list.

Package-Manager: Portage-2.3.24, Repoman-2.3.6