[Support] Update gathering-information-for-troubleshooting-sites.mdx

[luishcardoso]

Hello team,

Summary

Can we link Cloudflare page on Traceroute (MTR) here as well? https://www.cloudflare.com/en-gb/learning/network-layer/what-is-mtr/

Thanks!

[ngayerie]

Hi @angelampcosta Could you please merge this one? Thanks!