bug(drag-drop): Slot content not visible when we start dragging an element

### Is this a regression?

- [ ] Yes, this behavior used to work in the previous version

### The previous version in which this bug was not present was

_No response_

### Description

Hi,

Background:
I am creating a reusable dynamic list component which also has the ability to drag and drop items in a list.
This component uses **slots** to dynamically project content from the consumer component.

Problem:
The component renders correctly.
But when I start dragging an item, the content in the slot is not visible.

Does anyone know how to solve this issue or any workaround for this?

@angular/cdk
@angular/cdk/drag-drop

Thanks!

### Reproduction

StackBlitz link: https://stackblitz.com/edit/stackblitz-starters-jbsaba?file=src%2Fmain.ts
Steps to reproduce:
1. Click on "Item 1 in slot" and start dragging it.
2. Notice that the text "Item 1 in slot" is not visible while you are dragging the item.

### Expected Behavior

Any content in a slot element should be visible while dragging the element.

### Actual Behavior

Content in the slot is not visible while you are dragging the item.

### Environment

- Angular: 16.2.7
- CDK/Material: 16.2.6
- Browser(s): Chrome
- Operating System: macOS

### REASON -
I am still debugging but found the reason behind this problem.
As per documentation,
"When a cdkDrag element is picked up, it will create a preview element visible while dragging."
This causes another slot element to be created with the same name which is why we don't see its content.

Still trying to find a solution.

Ouvrez la reproduction StackBlitz liée et commencez par src/main.ts. Faites glisser « Item 1 in slot » pour confirmer que le contenu de slot projeté est absent de l’aperçu du glissement. C’est terminé lorsque le texte du slot reste visible pendant le glissement et que les étapes de reproduction passent toujours.

Rédigé par le modèle d'indexation à partir du texte de l'issue.