Improve performance of deleting blocks

[BeksOmega]

Check for duplicates

• I have searched for similar issues before opening a new one.

Description

Deleting the top block of the spaghetti code stack on master (4125fd3) takes ~1670ms, and checkAndDelete takes ~1000ms.

On develop (c093421) it takes ~720 seconds, with checkAndDelete taking ~360ms.

Reproduction steps

1. Go to the playground
2. Hit the "spaghetti" or "JSO spaghetti" test buttons.
3. Go to the performance tab of the chrome devtools.
4. Start a recording
5. Delete the top block in the spaghetti stack.
6. Stop the recording.

Stack trace

No response

Screenshots

No response

Browsers

No response