Error when visiting rpm packages

```
purldb-visitor-1 | ERROR:minecode.management.commands.run_visit:Visit error for URI: rsync://mirrors.kernel.org/centos/
purldb-visitor-1 | TypeError TypeError('must be real number, not str')
purldb-visitor-1 | Traceback (most recent call last):
purldb-visitor-1 | File "/app/minecode/management/commands/run_visit.py", line 255, in visit_uri
purldb-visitor-1 | new_uris_to_visit, visited_data, visit_error = _visit_router.process(uri_to_visit)
purldb-visitor-1 | File "/app/minecode/route.py", line 164, in process
purldb-visitor-1 | return endpoint(string, *args, **kwargs)
purldb-visitor-1 | File "/app/minecode/visitors/repodata_rpms.py", line 53, in collect_repomd_urls
purldb-visitor-1 | directory_listing = rsync.fetch_directory(uri)
purldb-visitor-1 | File "/app/minecode/rsync.py", line 151, in fetch_directory
purldb-visitor-1 | raise Exception('%(cmd) failed. rc:%(tc)d err: %(err)s' % locals())
purldb-visitor-1 | TypeError: must be real number, not str
```