Test block and test instance block menus have blurred backgrounds

The Bug:

Test block and test instance block menus have blurred backgrounds.

Similar menus such as command blocks, structure blocks, and jigsaw blocks don't have blurred backgrounds therefore introducing an inconsistency.

Steps to Reproduce:

1. Place down a test block or a test instance block.

2. Open it up and observe if the background is blurred.

Observed Behavior:

The background is blurred.

Expected Behavior:

The background would not be blurred.