Tabs block: Do not render empty tabs #84049

Description

when you insert a new tabs block, it's empty by default.
But if you save and look at the front end, it still get's rendered. I think this shouldn't be the case, the same as empty paragraphs or headings are not displayed.

The same goes for the accordion block. If someone picks this issue here up, we can create another separate issue

Step-by-step reproduction instructions

1. insert a new tabs block, do not enter information
2. save the page
3. inspect the page

Screenshots, screen recording, code snippet

Environment info

• WP 7.1.2
• GB 24.1.0

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

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure