fix: Ensure the "fix" command does not display when Duo is disabled

Description

Hides the Fix command when Duo features are disabled for a project.

This is inline with how other commands work.

Related Issues

Resolves #1574 (closed)

How has this been tested?

• Open a project which does not have Duo features available (e.g. explicitly disabled or a personal project)
• Ctrl+shift+p to open command palette
• Type Duo to see all available Duo commands
• List should be empty

Screenshots (if appropriate)

What CHANGELOG entry will this MR create?

• fix: Bug fix fixes - a user-facing issue in production - included in changelog
• feature: New feature - a user-facing change which adds functionality - included in changelog
• BREAKING CHANGE: (fix or feature that would cause existing functionality to change) - should bump major version, mentioned in the changelog
• None - other non-user-facing changes

Closes #1574 (closed)