Baking sets dont load properly if lighting data is cleared

Steps to reproduce:

1. Update the local path in the manifest.json file. Im using local trunk.
2. Open the spotlight project on APV project branch https://github.com/iM0ve/Spotlight-HDRP/tree/APV
3. Load any scene. For example the Main and Day scenes.
4. Click on Lighting tab ->Adaptive Probe volumes

Actual results: 

Error in the console and the mode is incorrect. It shows single scene.

Expected results: 

No error. Mode is Baking Set.

Reproducible with versions: 

6.2.0a7

Notes:

• It only happens if the project has no baked lighting data or it was cleared and the project was closed.
• It is possible to "fix" the project by trying to rebake the lighting, however you will have to press cancel on 3 popups (for each scene in the baking set). After the bake is complete the correct baking set will be displayed.
• Possibly related to another bug [Internal link]