[redhat-documentation/vale-at-red-hat]: Enhance the installation instructions

[tmalove]

Description: As part of the vale-at-red-hat working user group initiative, we have identified improvements and enhancements to the existing user guide. These enhancements will provide detailed instructions to guide the user through the installation process.

Solution: Migrate the verified content (in the Installing Vale client with the vale-at-red-hat rules) into the the existing guide.

Additional context: As discussed in the vale-at-red-hat Slack channel and the recent Open Office hours workgroup, to provide a CCS vale-at-red-hat onboarding toolkit.

[tmalove]

@michelle-purcell I am starting at the bottom of the installation instructions, creating the modules.