Delete unused preference setting

shared/src/commonMain/kotlin/bou/amine/apps/readerforselfossv2/service/AppSettingsService.kt

@@ -21,7 +21,6 @@ class AppSettingsService(acraSenderServiceProcess: Boolean = false) {
     private var _displayUnreadCount: Boolean? = null
     private var _displayAllCount: Boolean? = null
     private var _fullHeightCards: Boolean? = null
-    private var _updateSources: Boolean? = null
     private var _periodicRefresh: Boolean? = null
     private var _refreshWhenChargingOnly: Boolean? = null
     private var _infiniteLoading: Boolean? = null
@@ -223,16 +222,7 @@ class AppSettingsService(acraSenderServiceProcess: Boolean = false) {
         }
         return _fullHeightCards == true
     }
-    private fun refreshUpdateSourcesEnabled() {
-        _updateSources = settings.getBoolean(UPDATE_SOURCES, true)
-    }
 
-    fun isUpdateSourcesEnabled(): Boolean {
-        if (_updateSources != null) {
-            refreshUpdateSourcesEnabled()
-        }
-        return _updateSources == true
-    }
     private fun refreshPeriodicRefreshEnabled() {
         _periodicRefresh = settings.getBoolean(PERIODIC_REFRESH, false)
     }
@@ -393,7 +383,6 @@ class AppSettingsService(acraSenderServiceProcess: Boolean = false) {
         refreshDisplayUnreadCountEnabled()
         refreshDisplayAllCountEnabled()
         refreshFullHeightCardsEnabled()
-        refreshUpdateSourcesEnabled()
         refreshPeriodicRefreshEnabled()
         refreshRefreshWhenChargingOnlyEnabled()
         refreshRefreshMinutes()
@@ -492,8 +481,6 @@ class AppSettingsService(acraSenderServiceProcess: Boolean = false) {
 
         const val FULL_HEIGHT_CARDS = "full_height_cards"
 
-        const val UPDATE_SOURCES = "update_sources"
-
         const val PERIODIC_REFRESH = "periodic_refresh"
 
         const val REFRESH_WHEN_CHARGING = "refresh_when_charging"