fix: support IDNA in lists

[ThinkChaos]

Not sure this is actually supported by most adblocker, but we might as well be permissive.

Fixes #961.

[codecov]

Codecov Report

Patch coverage: 82.35% and project coverage change: -0.04 ⚠️

Comparison is base (30ead04) 93.64% compared to head (9a9681d) 93.60%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #963      +/-   ##
==========================================
- Coverage   93.64%   93.60%   -0.04%     
==========================================
  Files          63       63              
  Lines        5304     5320      +16     
==========================================
+ Hits         4967     4980      +13     
- Misses        264      266       +2     
- Partials       73       74       +1     

Impacted Files	Coverage Δ
lists/parsers/hosts.go	97.72% <82.35%> (-2.28%)	⬇️

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[ThinkChaos]

The only line not covered is just a return "", err.
Not sure how to trigger an error with idna.Punycode, so I'd just ignore that hole here.

[0xERR0R]

LGTM 👍