removed unnecessary route parameter

Fixes non-existant parameter in services.yml.  Fixes #29. Was commited unintentionally [here](https://github.com/kmfk/qpush-bundle/commit/8102857bf8208e5262f7346df323c9ce86e8dd0e#diff-24d25eb5e07008bbf94172e9c1049950R31)

I'll update unit tests a little bit later to avoid this sort of thing in the future.