#17489 Hide clone panel from guests

What does this MR do?

1. Adds permission conditional to the clone panel at a component level.

2. Conditionally removes the .clone-row on the project home panel to avoid whitespace when the clone panel component returns null for an unauthorized user.

3. Adds the :download_code permission conditional to the download button at a component level.

Are there points in the code the reviewer needs to double check?

No

Why was this MR needed?

Stops guest users and unauthorized users from seeing code download components.

What are the relevant issue numbers?

Fixes #17489 (closed).

Screenshots