refactor: reduce strictness of Stream Deck path checking

[GeekyEggo]

On some occasions it may not be possible to determine where Stream Deck was installed. As this function is only use as an informative indicator, and there is no critical path, the checks should be loosened to be less reliant on the exact location.

[tiptronic]

@GeekyEggo Fully agree! Just a quick note, because you're checking the Windows path more thoroughly:
On the Mac:

• an application could (generally) live everywhere (inside or outside the /Applications directory).
• it could be a symlink or an alias
• it generally doesn't even have to be named 'Elgato Stream Deck.app'