I debugged the problem, and executed the test in my machine, and this is the test output I got:
layout_builder_system_breadcrumb_alter(Object, Object, Array) (Line: 539)
Drupal\Core\Extension\ModuleHandler->alter('system_breadcrumb', Object, Object, Array) (Line: 94)
Drupal\Core\Breadcrumb\BreadcrumbManager->build(Object) (Line: 72)
Drupal\system\Plugin\Block\SystemBreadcrumbBlock->build() (Line: 163)
Drupal\block\BlockViewBuilder::preRender(Array)
call_user_func('Drupal\block\BlockViewBuilder::preRender', Array) (Line: 378)
Drupal\Core\Render\Renderer->doRender(Array) (Line: 450)
Drupal\Core\Render\Renderer->doRender(Array, 1) (Line: 195)
Drupal\Core\Render\Renderer->render(Array, 1) (Line: 151)
Drupal\Core\Render\Renderer->Drupal\Core\Render\{closure}() (Line: 582)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 152)
Drupal\Core\Render\Renderer->renderPlain(Array) (Line: 166)
Drupal\Core\Render\Renderer->renderPlaceholder('', Array) (Line: 693)
Drupal\big_pipe\Render\BigPipe->renderPlaceholder('', Array) (Line: 434)
Drupal\big_pipe\Render\BigPipe->sendNoJsPlaceholders('', Array, Object) (Line: 336)
Drupal\big_pipe\Render\BigPipe->sendPreBody('', Array, Object) (Line: 304)
Drupal\big_pipe\Render\BigPipe->sendContent(Object) (Line: 112)
Drupal\big_pipe\Render\BigPipeResponse->sendContent() (Line: 374)
Symfony\Component\HttpFoundation\Response->send() (Line: 20)
After making changes in layout_builder module, the tests worked. I am not sure whether the problem is in the big_pipe module, or the test framework.