Remove references to privacy level 4 (no longer functional)

[PromoFaux]

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• I have made only one major change in my proposed changes.
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What does this PR aim to accomplish?:

Closes #3802

[dschaper]

I'd like Dom's approval before merging in. It makes sense to me but it seems like something we shouldn't have missed and maybe there's a reason we didn't.

[DL6ER]

All good, just too many places in the code where this was written. With level 4, blocking doesn't work because we cannot look up a donation in the database when we do not process the queries in the first place. This was possible before v5, because we loaded all domains into the DNS cache.

[PromoFaux]

because we cannot look up a donation in the database

Did your phone autocorrect domain to donation??

[pralor-bot]

This pull request has been mentioned on Pi-hole Userspace. There might be relevant details there:

https://discourse.pi-hole.net/t/pi-hole-core-web-v5-2-and-ftl-v5-3-released/40909/1