Update Linux development dependencies

[Seekers2001]

Description

Add libffi-dev and libyaml-dev to the Linux development dependency command. These packages are needed when building the Ruby dependencies used by a fresh Metasploit development environment.

Related Issue: Fixes #21669

Breaking Changes

None

Verification Steps

1. Open docs/metasploit-framework.wiki/dev/Setting-Up-a-Metasploit-Development-Environment.md.
2. Find the Linux command under Install dependencies.
3. Confirm that the command installs both libffi-dev and libyaml-dev before the later bundle install step.

Test Evidence

• git diff --check passes.
• The updated command was checked directly for both package names.
• tools/dev/msftidy_docs.rb was also run, but it is scoped to module documentation and rejects this pre-existing wiki guide as "Doc missing module"; its module-section warnings are not applicable to this file.

Environment

Field	Details
Operating System	macOS (documentation-only change)
Target Software/Hardware	Apt-based Linux development environments

AI Usage Disclosure

OpenAI Codex (GPT-5) was used to inspect the issue and repository guidance, make the one-line documentation edit, and run the checks listed above.

Pre-Submission Checklist

• Included a corresponding documentation markdown file in documentation/modules (new modules only)
• No sensitive information (IP addresses, credentials, API keys, hashes) in code or documentation
• Tested on the target environment specified in the Environment section above
• Included RSpec tests for library changes (encouraged for lib/ changes)
• Read the CONTRIBUTING.md and module acceptance guidelines