Comment 1 for bug 315770

As discussed on IRC, it's trivial to remove the need for these packages in main by demoting libio-socket-ssl-perl instead; so I'm dropping the build-depends-indep on that package from libnet-ldap-perl, since it only needs it for an optional test suite. Since we aren't making any other changes to libnet-ldap-perl, we'll take the risk that TLS will manage to be broken on Ubuntu but not Debian for just this one package.