fix: hide create playlist drop box when dragging a rundown not in a multi-rundown playlist SOFIE-2462

[Julusian]

About the Contributor

This pull request is posted on behalf of the NRK.

Type of Contribution

This is a: Bug fix

Current Behavior

In the rundown list page, when dragging a rundown which is not grouped in a playlist, a dropbox is shown to create it in a new playlist. This has no visible effect, as the rundown is moved into a non-grouped playlist, giving the same result as before.

New Behavior

When dragging a rundown which is alone in a flattened playlist, don't show the drop box

Testing

• [ ] I have added one or more unit tests for this PR
• [ ] I have updated the relevant unit tests
• [x] No unit test changes are needed for this PR

Affected areas

This is a minor ui change

Other Information

Status

• [x] PR is ready to be reviewed.
• [x] The functionality has been tested by the author.
• [ ] Relevant unit tests has been added / updated.
• [ ] Relevant documentation (code comments, system documentation) has been added / updated.