Merge pull request #16889 from rgacogne/ddist-add-health-check-validation-callback

dnsdist: Add a Lua callback to validate health-check responses

diff --cc pdns/dnsdistdist/dnsdist-configuration-yaml.cc
Simple merge

diff --cc pdns/dnsdistdist/dnsdist-healthchecks.cc
Simple merge

diff --cc pdns/dnsdistdist/dnsdist-lua.cc
Simple merge

diff --cc pdns/dnsdistdist/dnsdist-settings-definitions.yml
Simple merge

diff --cc pdns/dnsdistdist/dnsdist.hh
Simple merge

diff --cc pdns/dnsdistdist/docs/reference/config.rst
Simple merge