test [nfc]: Use eg.globalStore when possible

Later we will add more required parameters to TestGlobalStore.

Signed-off-by: Zixuan James Li <zixuan@zulip.com>

Author: PIG208

test/model/binding.dart

@@ -12,6 +12,7 @@ import 'package:zulip/model/binding.dart';
 import 'package:zulip/model/store.dart';
 import 'package:zulip/widgets/app.dart';
 
+import '../example_data.dart' as eg;
 import 'test_store.dart';
 
 /// The binding instance used in tests.
@@ -86,7 +87,7 @@ class TestZulipBinding extends ZulipBinding {
   ///
   /// Tests that access this getter, or that mount a [GlobalStoreWidget],
   /// should clean up by calling [reset].
-  TestGlobalStore get globalStore => _globalStore ??= TestGlobalStore(accounts: []);
+  TestGlobalStore get globalStore => _globalStore ??= eg.globalStore();
   TestGlobalStore? _globalStore;
 
   bool _debugAlreadyLoadedStore = false;

test/model/store_test.dart

@@ -400,7 +400,7 @@ void main() {
     late FakeApiConnection connection;
 
     Future<void> prepareStore({Account? account}) async {
-      globalStore = TestGlobalStore(accounts: []);
+      globalStore = eg.globalStore();
       account ??= eg.selfAccount;
       await globalStore.insertAccount(account.toCompanion(false));
       connection = (globalStore.apiConnectionFromAccount(account)
@@ -575,7 +575,7 @@ void main() {
     }
 
     Future<void> preparePoll({int? lastEventId}) async {
-      globalStore = TestGlobalStore(accounts: []);
+      globalStore = eg.globalStore();
       await globalStore.add(eg.selfAccount, eg.initialSnapshot(
         lastEventId: lastEventId));
       await globalStore.perAccount(eg.selfAccount.id);