[Mac] Allow setting the prefixes folder on Mac too

[arielj]

This option is present only on Linux, but we should also allow users to set this on Mac for the "wines" that work with prefixes like Wine-Staging.

Currently the prefixes dir is the default ~/Games/Heroic/Prefixes/default and can't be changed.

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Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)

[flavioislima]

Looks good, but what is being shown if the selected wine is Crossover?

[arielj]

Looks good, but what is being shown if the selected wine is Crossover?

This setting is shown in the general settings, it's independent of what's selected as the wine for a given game. (like in linux it's independent to games being win or native)

[flavioislima]

Looks good, but what is being shown if the selected wine is Crossover?

This setting is shown in the general settings, it's independent of what's selected as the wine for a given game. (like in linux it's independent to games being win or native)

Ah ok, I misread the name of the file for the one we show on the game settings.
Should be fine then.