feat: ucc-gen validate command support

[hetangmodi-crest]

Issue number:
ADDON-76818

PR Type

What kind of change does this PR introduce?

• Feature
• Bug Fix
• Refactoring (no functional or API changes)
• Documentation Update
• Maintenance (dependency updates, CI, etc.)

Summary

Changes

Introduced a new command ucc-gen validate, which will validate the user provided add-on using splunk-appinspect. For now, we have only included cloud tag while validating add-ons.

User experience

Users will now be able to validate their apps and add-ons during development time to ensure that their add-on meets
Splunk's standards and best practices.

ucc-gen validate --addon-path <path_for_addon>

Checklist

If an item doesn't apply to your changes, leave it unchecked.

Review

• self-review - I have performed a self-review of this change according to the development guidelines
• Changes are documented. The documentation is understandable, examples work (more info)
• PR title and description follows the contributing principles
• meeting - I have scheduled a meeting or recorded a demo to explain these changes (if there is a video, put a link below and in the ticket)

Tests

See the testing doc.

• Unit - tests have been added/modified to cover the changes
• Smoke - tests have been added/modified to cover the changes
• UI - tests have been added/modified to cover the changes
• coverage - I have checked the code coverage of my changes (see more)

Demo/meeting:

Reviewers are encouraged to request meetings or demos if any part of the change is unclear

[github-actions]

Code Coverage 🎉

Type	PR	Develop	Change	Status
Line Coverage	88.28%	88.26%	0.02%	🟢 Increased
Branch Coverage	81.89%	81.93%	0.05%	🔴 Decreased