android: Fix closing a game launched from a home screen shortcut (#2658)

Shortcuts set the launchedFromShortcut extra, but EmulationActivity
checked launched_from_shortcut, so finishAffinity() never ran and
closing the game returned to the game list instead of the home screen.

src/android/app/src/main/java/org/citra/citra_emu/activities/EmulationActivity.kt

@@ -74,7 +74,7 @@ class EmulationActivity : AppCompatActivity() {
     lateinit var secondaryDisplayManager: SecondaryDisplay
 
     private val onShutdown = Runnable {
-        if (intent.getBooleanExtra("launched_from_shortcut", false)) {
+        if (intent.getBooleanExtra("launchedFromShortcut", false)) {
             finishAffinity()
         } else {
             this.finish()