When there is no account, do not render buttons in connect hardware flow

### Describe the bug

If there is no account then the button should not be rendered.

This was a nit from https://github.com/MetaMask/metamask-extension/pull/17610. That incremental improvement has been merged, but we would still like to request that this be further enhanced.

### Steps to reproduce

From https://github.com/MetaMask/metamask-extension/issues/14896:

Steps to reproduce
1. Unlock Metamask
2. Unfold Menu
3. Click Connect Hardware Wallet
4. Click Ledger and wait

### Error messages or log output

_No response_

### Version

10.30.4

### Build type

None

### Browser

Chrome, Firefox

### Operating system

MacOS

### Hardware wallet

_No response_

### Additional context

_No response_

Reproduce the listed connect hardware wallet flow, checking the Ledger screen when no account is available. Done means the buttons are not rendered in that state; the issue names no file or test, so locate the existing flow and its coverage before changing it.

Written by the indexing model from the issue text.