Grid: Don't highlight grid cell if block being dragged is not allowed to be placed into the Grid #63979
Description
When you drag a block over a Grid, we highlight the cell that you're hovering over.
We should not do this when the block you're dragging can't be inserted into a Grid. For example, you can't put a Button block into a Grid. (You can only put a Button block into a Buttons block.)
Example:
Kapture.2024-07-26.at.15.12.27.mp4
The empty cells shouldn't turn blue.
I believe there's already selectors for this e.g. canInsertBlockType.