Merge pull request #7933 from rgacogne/dnsdist-doh-http-stats

dnsdist: Add more stats about DoH HTTP responses

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

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

diff --cc pdns/dnsdistdist/doh.cc
Simple merge

diff --cc pdns/doh.hh
Simple merge