fix: Less flaky auto-fetch

[lissy93]

Summary

• Make domain updater more reliable: Longer timeouts, shared timeout budget, no retries for obvious failures
• Fixes a regression in registrar name normalization
• Adds troubleshooting docs for fixing domain update failures/timeouts
• Keep and use whois answer for lookups when the registrar referral is dead

Related

Fixes #93
Fixes #87
Fixes #48
Fixes #76

Checklist

• I've tested this change
• I've followed the coding style and contribution guidelines
• I've updated documentation (if needed)
• I've confirmed this change is backwards compatible / won't break anything