[Documentation] update instructions.md for self-certification participants (v2.0.0-beta)

[lixuna]

Describe the update: update instructions for self-certification participants

Describe why update is needed

• CNF WG (and CNCF’s related Cloud Native Telco efforts) has moved to LFN (see wiki)
• what we have now: https://github.com/lfn-cnti/certification/blob/main/instructions.md

Tasks

• [x] Draft new instructions based on new CNTI Certification process
• [ ] update section called The Tests
• [x] update section called Prereqs
• [x] update section called Running
• [x] update section called Uploading
• [x] Update email address in section called Review - If you don't see a response within 5 business days, please send an email to [email protected].
• [x] Update email address in section called Issues - Questions and comments can also be sent via email to [email protected].