Fix fetch-on-startup logic

The fetch-on-startup would only happen if the metered state was
explicitly set to "No".  Hence, when the state is "Unknown" (which will
happen in most cases) no fetching would be done on startup.

The new logic will check for the metered state not being equal to "Yes".

src/qml/main.qml

@@ -65,7 +65,7 @@ Kirigami.ApplicationWindow {
 
         // Refresh feeds on startup if allowed
         if (SettingsManager.refreshOnStartup) {
-            if (SettingsManager.allowMeteredFeedUpdates || NetworkStatus.metered === NetworkStatus.No) {
+            if (SettingsManager.allowMeteredFeedUpdates || NetworkStatus.metered !== NetworkStatus.Yes) {
                 Fetcher.fetchAll();
             }
         }