(MODULES-11704) Add Puppet 9 support

[imaqsood]

Summary

Adds Puppet 9 support to puppetlabs-java, mirroring the completed work in puppetlabs-motd / inifile / apache.

Changes

• metadata.json — puppet requirement kept at >= 8.0.0 < 10.0.0. Pruned EOL / no-agent platforms and refreshed the supported OS list:
  • Removed CentOS (all) and OracleLinux (only had 7).
  • Removed RedHat 7, Debian 10, SLES 12, Ubuntu 18.04.
  • Added RedHat 10; Debian 13 already present.
  • Final OS list: RedHat 8/9/10, Debian 11/12/13, Ubuntu 20.04/22.04/24.04, SLES 15, Rocky 8, AlmaLinux 8.
• Gemfile (VARIANT A) — added the puppet9_stream flag; replaced the earlier partial if puppet_version...8.99|9 puppet/facter block with the canonical one (facter now ['>= 4.11', ...]) resolving Puppet 9 prerelease gems from PUPPET_GEM_SOURCE (falling back to puppetcore when empty). Gated the newer lint stack behind the Puppet 9 (8.99.x) stream: voxpupuli-puppet-lint-plugins ~> 7.0, puppetlabs_spec_helper from a git branch, and puppet_litmus from a git branch when PUPPET_FORGE_TOKEN is set (released ~> 2.0 fallback otherwise). puppet-lint 4.x crashes on Ruby 3.4+, so 7/8 keep the released versions.
• Rakefile — disabled strict_indent (its expected indentation differs incompatibly between the 7/8 and 9 lint lanes).
• .github/workflows/ci.yml — Spec job now uses cat-github-actions ...module_ci.yml@MODULES-11700-puppet9-gem-source, installs libcurl4-openssl-dev (patron native extension), and inherits secrets. Acceptance flags now exclude ubuntu-20.04 from the Puppet 9 lane only (--collection-platform-exclude 9:ubuntu-20.04).
• manifests/download.pp — added a trailing comma required by the puppet-lint 5.x trailing_comma check (Puppet 9 lane); no behaviour change.

Temporary branch dependencies

• puppetlabs_spec_helper → MODULES-11700-allow-puppet-lint-5 (allows puppet-lint 5.x)
• puppet_litmus → MODULES-11700-collection-platform-exclude (adds --collection-platform-exclude to matrix_from_metadata_v3)
• cat-github-actions → @MODULES-11700-puppet9-gem-source

Local verification

• OLD lane (Puppet 8, Ruby 3.1.1): rake lint exit 0; unit specs 195 examples, 0 failures.
• NEW lane (Puppet 9 lint tooling, Ruby 3.4.6, forced lint5): rake lint exit 0.

https://perforce.atlassian.net/browse/MODULES-11704