Client unable to fetch URLs with comma

[demanuel]

How to reproduce:

> my $resp = await Cro::HTTP::Client.get('https://lobste.rs/t/ai,compsci.rss')
An operation first awaited:
  in block <unit> at <unknown file> line 1

Died with the exception:
    Server responded with 404 Not Found
      in block  at /home/demanuel/.raku/sources/5DF05A37EADB5F570EBCC5CA4E892D3D8C93E425 (Cro::HTTP::Client) line 673

while with curl there's no issue whatsoever.