feat: add serverless auto-issue function

[alexiscolin]

This aims to link a bot to create issue without GH account.

Fixes: https://github.com/allinbits/multiwallet/issues/46

Need Netlify and GH Bot to be setup properly.

---

The Token API used in .env comes from a GitHub App bot that I'll be able to transfer to AiB.
Issues can be created outside of GH without credentials by using this request.

curl -X POST https://wallet-security-lists.netlify.app/.netlify/functions/createissue \
  -H "Content-Type: application/json" \
  -d '{
    "type": "Site",
    "data": {
      "name": "Malicious Phishing Site",
      "url": "phishing-url.com",
      "user-note": "This site is attempting to phish user credentials.",
      "threat-level": "3 (High) Site should not be allowed under any circumstances"
    }
  }'