fix: properly initialize hideUnimportantStateEvents setting

This setting was not applied on app restart but always initialized to
the default value. The only way change this was to go into settings and
change the toggle twice after an app restart.

lib/widgets/matrix.dart

@@ -423,6 +423,10 @@ class MatrixState extends State<Matrix> with WidgetsBindingObserver {
         store.getBool(SettingKeys.hideUnknownEvents) ??
             AppConfig.hideUnknownEvents;
 
+    AppConfig.hideUnimportantStateEvents =
+        store.getBool(SettingKeys.hideUnimportantStateEvents) ??
+            AppConfig.hideUnimportantStateEvents;
+
     AppConfig.separateChatTypes =
         store.getBool(SettingKeys.separateChatTypes) ??
             AppConfig.separateChatTypes;