tpa-rfc-73: add references to Puppet Server

policy/tpa-rfc-73-tails-infra-merge-roadmap.md

@@ -330,7 +330,9 @@ This proposal is about:
 - **Constraints:**
   - Blocked by Tor upgrade to Puppet 7
   - Blocks everything we'll "keep", plus Backups, TLS, Monitoring, Firewall, Authentication
-- **References:** ∅
+- **References:**
+  - tpo/tpa/team#41948
+  - [TPA-RFC-77: Tails and TPA Puppet codebase merge](/tpo/tpa/team/-/wikis/policy/tpa-rfc-77-puppet-merge)
 
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