Switched the Shortcut component to use global MODIFIER_KEY

What does this MR do and why?

The MR refactors how we get the modifier key on different platforms to use the global constant instead of the custom snippet in the component.

Screenshots or screen recordings

	Before	After
MacOS
Windows

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #385852 (closed)