[playground] Remove button from error message

We show the entire error in panel, no need to click to console.log 

This makes it easier to copy the error now. 

Before: 


https://github.com/facebook/react-forget/assets/565765/4c13abfe-a06d-4580-b3d7-b02792f53e57 

After: 


https://github.com/facebook/react-forget/assets/565765/0dff95cc-5207-48a5-a0b6-2055cadcb780