Improve error handling for DNS timeouts and clean terminal output

[mrvcode]

​"Hi! I've noticed that when a nameserver fails to respond (e.g., due to a firewall or connection timeout), the tool sometimes masks the error or displays a generic poisoning message.
​I have updated dnsvalidator.py to:
​Capture specific connection errors: It now displays the actual exception (like 'Resolution lifetime expired') instead of just failing.
​Clean up output: Removed redundant strings from the dnspython exceptions to keep the terminal logs readable.
​This change helps security researchers distinguish between a truly malicious DNS response and simple network connectivity issues during large scans."

[mrvcode]

Hi @vortexau / maintainers,
Just wanted to gently bump this PR — I noticed there’s been some recent activity on other PRs (#51, #52), so I’m hoping this one might also get reviewed soon.
This change improves error clarity for DNS timeouts and cleans up terminal output, which helps during large-scale scans. Happy to adjust if needed!
Thanks for maintaining this tool — it’s super useful!