Add simp/rsync module to harness

[jst-cyr]

Module

• Forge: https://forge.puppet.com/modules/simp/rsync
• GitHub: https://github.com/simp/pupmod-simp-rsync
• Forge name / version: simp-rsync 8.0.0
• Puppet requirement: puppet >=8 <9
• OS support: RHEL-family 8/9/10 (RedHat, CentOS, OracleLinux, Rocky, AlmaLinux)

Summary

simp/rsync was evaluated for the compatibility harness. It is a viable Puppet
Core 8 candidate, and — unlike the other SIMP modules — it does ship Docker
nodesets plus a single-SUT default. However, its functional acceptance suites
require two or more SUTs, which the harness's single-SUT Docker model cannot
provide.

Because upstream acceptance tests exist but can't be fully exercised here,
onboarding now would mean an acceptance: blocked entry, which the dashboard's
is_fully_compatible() gate excludes from KNOWN_COMPATIBLE.md by design (see
scripts/render_status_dashboard.py). This issue queues the module for onboarding
once the harness gains multi-host acceptance support.

Acceptance blocker

• Ships Docker nodesets and a single-SUT default nodeset (00_default_spec.rb
  would run on one container).
• But the functional suites carry the real coverage and need ≥2 hosts:
  • 10_server_client_spec and 20_server_client_stunnel_spec call
    unique_host_pairs(hosts) and skip unless hosts.count >= 2, testing
    bidirectional server/client transfers between distinct SUTs.

Notes

• Declares puppet as the dependency name (not openvox).
• Depends on simp-beaker-helpers (~> 3.1) in the :system_tests group, which
  adds bootstrap complexity for any future acceptance wiring.
• OS targets are fine: the harness already has el9, el9-systemd, and el10
  setfiles. The blocker is topology (multi-host), not OS.

Proposed action

• Onboard simp/rsync (unit + acceptance) once ≥2-SUT acceptance is supported.
• Alternatively, add now as acceptance: blocked if unit-only signal is
  deemed worth the per-run time (accepts permanent "not fully compatible"
  status).