Improve autosaveDelay test stability

After looking at CI tests in pull request keepassxreboot#9100 the margin for the file save delay was too short.
This commit extends the margin to 10 seconds and simplifies the test.

tests/gui/TestGui.cpp

@@ -1560,6 +1560,7 @@ void TestGui::testDatabaseSettings()
     // 2.e) Save changes
     editEntryWidget->setCurrentPage(0);
     editEntryWidgetButtonBox = editEntryWidget->findChild<QDialogButtonBox*>("buttonBox");
+    QDateTime lastEntryModifiedTime = QDateTime::currentDateTime();
     QTest::mouseClick(editEntryWidgetButtonBox->button(QDialogButtonBox::Ok), Qt::LeftButton);
 
     // 3 Double check both true negative and true positive
@@ -1569,11 +1570,10 @@ void TestGui::testDatabaseSettings()
     QCOMPARE(fileInfo.lastModified(), lastModified);
 
     // 3.b) Test modification time after expected
-    int marginDelay = 500; // error margin to account for extra delays (ms)
-    Tools::wait(autosaveDelayTestValue * 60 * 1000 / 2 + marginDelay / 2);
+    int marginDelay = 10000; // error margin to account for extra save delays (ms)
+    Tools::wait(autosaveDelayTestValue * 60 * 1000 / 2 + marginDelay);
     fileInfo.refresh();
-    QVERIFY2(fileInfo.lastModified().msecsTo(QDateTime::currentDateTime()) < marginDelay,
-             "AutosaveDelay: wrong timing");
+    QVERIFY2(fileInfo.lastModified() >= lastEntryModifiedTime, "AutosaveDelay: wrong timing");
 
     // 4 cleanup
     config()->set(Config::AutoSaveAfterEveryChange, false);