simplifying a button visibility check

app/src/main/kotlin/com/simplemobiletools/calculator/activities/SettingsActivity.kt

@@ -36,7 +36,7 @@ class SettingsActivity : SimpleActivity() {
     }
 
     private fun setupPurchaseThankYou() {
-        settings_purchase_thank_you_holder.beVisibleIf(!isOrWasThankYouInstalled())
+        settings_purchase_thank_you_holder.beGoneIf(isOrWasThankYouInstalled())
         settings_purchase_thank_you_holder.setOnClickListener {
             handleCustomizeColorsClick()
         }