docs: fix code of conduct link in issue template

[Lovlace777]

Summary

• Updates the documentation issue template to link to this repository's Code of Conduct.
• Replaces the old appwrite/appwrite URL, which redirects to a missing page.
• Keeps the change limited to the issue template URL.

Validation

• curl.exe -L -I https://github.com/appwrite/appwrite/blob/master/CODE_OF_CONDUCT.md -> 404 after redirect to https://github.com/appwrite/appwrite/blob/main/CODE_OF_CONDUCT.md.
• curl.exe -L -I https://github.com/appwrite/runtimes/blob/main/CODE_OF_CONDUCT.md -> 200.
• PowerShell content check confirmed the new URL is present and the old URL is absent.
• git diff --check passed.
• composer validate --strict was not run because Composer is not available in the local PATH; this change only updates a GitHub issue-template link.

Notes

• Closes 📚 Documentation: Broken link to 'Code of Conduct' #90.
• No runtime code or compatibility impact.
• No follow-up work expected.

[greptile-apps]

Greptile Summary

• Updates .github/ISSUE_TEMPLATE/documentation.yaml to point the Code of Conduct link at this repository's CODE_OF_CONDUCT.md on main.
• Keeps the change scoped to the documentation issue template URL.

Confidence Score: 5/5

Safe to merge: the change is limited to a documentation issue-template link and does not affect runtime behavior.

The diff is small, scoped, and matches the stated intent of replacing a stale Code of Conduct URL with the repository-local document.

T-Rex Logs

What T-Rex did

• Viewed the pre-change diff artifact and confirmed line 29 referenced the master CODE_OF_CONDUCT.md URL, redirected to the main branch, and ended in a 404.
• Viewed the post-change diff artifact and confirmed line 29 now references the runtimes CODE_OF_CONDUCT.md URL on the main branch with a final status of 200.
• Noted that both diff artifacts reported exit code 0 and were limited to the line 29 URL replacement.

_{Ran code and verified through T-Rex}

_{Reviews (1): Last reviewed commit: "docs: fix code of conduct link in issue ..." | Re-trigger Greptile}