Merge pull request #8380 from rgacogne/ddist-default-openssl

dnsdist: Switch the default DoT provider from GnuTLS to OpenSSL

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

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

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