Image block: when override added, toolbar shows redundant separator

[annezazu]

Description

After setting an override in a synced pattern for an image block, I noticed the image block with the override shows a redundant separator in the block toolbar.

Step-by-step reproduction instructions

1. Create a synced pattern.
2. Add an image block.
3. Under Advanced in Block Settings, enable an override for the Image block.
4. Save and publish the synced pattern.
5. Create a new page or post.
6. Add the synced pattern with the override for the image block.
7. Select the image block in the synced pattern and notice the toolbar has an extra separator.

Screenshots, screen recording, code snippet

Environment info

• WP 6.5.3
• GB 18.4
• TT4
• Chrome Version 123.0.6312.107
• MacOS 14.1.1

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes