Safety Checkpoint for Downloading an Extension

[alyssacabading]

There could be a lot of malicious extensions that can be published in VSCode marketplace, with few of the extensions having blue check-verification of ownership. Whenever somebody downloads a non-verified extension, there should be a pop up warning along the lines of "This extension is does not have verified ownership. Are you sure you want to download [extension name]?"
I feel like there could be an added layer of error prevention from the user, because it makes the user more cognizant that non-verified extensions can come with risks when downloading it.
This builds on top of issue #52116, where not only do we want to ask users for permissions but we also want to warn users the risks of downloading extensions without the proper verification.

[alyssacabading]

Addressed by PR #235514