fix(config) fix prejoin throwing a TypeError due to late config initialization (#10041)

react/features/toolbox/functions.native.js

  */
 export function isToolboxVisible(stateful: Object | Function) {
     const state = toState(stateful);
-    const { toolbarConfig: { alwaysVisible } } = state['features/base/config'];
+    const { toolbarConfig } = state['features/base/config'];
+    const { alwaysVisible } = toolbarConfig || {};
     const { enabled, visible } = state['features/toolbox'];
     const participantCount = getParticipantCountWithFake(state);
     const alwaysVisibleFlag = getFeatureFlag(state, TOOLBOX_ALWAYS_VISIBLE, false);

react/features/toolbox/functions.web.js

  * otherwise.
  */
 export function isToolboxVisible(state: Object) {
-    const { iAmSipGateway, toolbarConfig: { alwaysVisible } } = state['features/base/config'];
+    const { iAmSipGateway, toolbarConfig } = state['features/base/config'];
+    const { alwaysVisible } = toolbarConfig || {};
     const {
         timeoutID,
         visible