Don't allow browser docks to arbitrarily close OBS

[WizardCM]

Description

This overrides the built-in window.close of Chromium with a no-op.

I tried alternatives that weren't as hacky, however they either aren't cancellable or didn't specify which frame made the request (or the reason for the close request).

Motivation and Context

Certain third party browser docks call window.close for whatever reason, which causes OBS to close. We don't approve.

How Has This Been Tested?

Open a browser dock.
Right click and Inspect.
Type window.close() in the Console.

Types of changes

• Tweak (non-breaking change to improve existing functionality)

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.