Check domains automatically

[scripthunter7]

Workflow:

1. Extract domains from adblock filtering rules to a set with AGTree
   • For example, extract
     • example.com from example.com###banner or
     • example.net from /ads.js^$domain=example.net or
     • example.org from ||example.org/test, etc.
2. Send a request to the domain and check the following:
   • does the request timeout?
   • is there a network error?
   • is the request redirected to a different domain?
3. Creating a scheduled GH actions workflow
   • call this workflow every week
   • it is enough to give a warning for potentially problematic domains, as the result of the check script requires a human review

[scripthunter7]

@ehrhardt06 Please note that we cannot check here the case if the content of the page changes to some random domain seller or other content, as the domaion and the website technically works in this case

[scripthunter7]

https://github.com/AdguardTeam/DeadDomainsLinter