fix(cli): wait for snapshot to be done

[y-lakhdar]

https://coveord.atlassian.net/browse/CDX-503

Proposed changes

Pulling a snapshot by its ID will cause an error since the command tries to download the snapshot in a pending state.
The fix is simply to add a waitUntilDone promise to make sure the snapshot is idle before manipulating it.

Testing

• Unit Tests:

• Functionnal Tests:

• Manual Tests:

1. Create a big snapshot.
2. Pull the snapshot while it is still pending.
3. It will show a spinner animation instead of breaking

CDX-503

[louis-bompart]

lgtm!