Remove not allowed chars from name before use as url.

Unfortunately, we have some gems that contains some chars that are not resolved as the URL pattern we have on the routes, so we cannot try to create a link out of them. Ideally we should not save those names, as we have a validation on the Rubygem model, however we still have some bad data in the db.

For instance this fix errors like the one is happening on https://rubygems.org/gems/pasaporte , which has a dependency with `camping>=1.5.180` as name.