skip remotes without url

If there is only a `pushurl` for a remote the `remote_urls` fails on `l.split("\t")[1].sub(/\s+\(.+?\)$/, '')` because the split results in only 1 part.

```bash
$ git remote -v
sonny	deploy@x.x.x.x:/usr/share/php/fetch-cms-core/source (push)
sonny
staging	deploy@x.x.x.x:/usr/share/php/fetch-cms-core/source (push)
staging
vito	deploy@x.x.x.x:/usr/share/php/fetch-cms-core/source (push)
vito
```