Fix Windows auto-update support detection

[smashwilson]

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Identify the Bug

Fixes #18559.

Description of the Change

The Windows-specific AutoUpdater class had a method that was not returning the result of a delegated call, which was causing it to erroneously enter the "unsupported" state when core.automaticallyUpdate was set to "false".

Alternate Designs

N/A

Possible Drawbacks

N/A

Verification Process

Set core.automaticallyUpdate to "false". Launch Atom on Windows and open the About window. The "Check now" button and "Automatically download updates" checkbox should be visible.

Release Notes

• Fixed a regression that caused Atom to believe it couldn't automatically update on Windows while core.automaticallyUpdate was set to "false".