knot-resolver: update to version 5.7.6

knot-resolver: update to version 5.7.6

Knot Resolver 5.7.6 (2025-07-17)
================================

Security
--------
- DoS: fix a rare segfault in `resolve` function (!1720)
  Someone controlling the DNS traffic might be able
  to trigger this crash intentionally and too often.
- DoS: drop a wrong assertion/crash (!1721)
  Someone controlling the DNS traffic will most likely be able
  to trigger this crash intentionally and too often.

Knot Resolver 5.7.5 (2025-04-24)
================================

Security
--------
- DoS: fix unconfirmed crashes with the line below (!1683)
  [system] requirement "h && h->end > h->begin" failed in queue_pop_impl

Improvements
------------
- tests: disable problematic config.http test (#925, !1678)
- validator: accept a confusing NODATA proof with insecure delegation (!1678)

Bugfixes
--------
- daemon/http: DoH stream got stuck after returning an error code (!1652)
- stats: request latency was very incorrect in some cases (!1678)

Signed-off-by: Vladimír Čunát <redacted>