Userland: Make Window::set_main_widget() non-fallible

Author: https://github.com/tcl3
Commit: 3aa49f268c
Pull-request: https://github.com/SerenityOS/serenity/pull/21152
Reviewed-by: https://github.com/kleinesfilmroellchen ✅

Userland/Libraries/LibGUI/ComboBox.cpp

@@ -116,7 +116,7 @@ ComboBox::ComboBox()
     m_list_window = add<Window>(window());
     m_list_window->set_window_type(GUI::WindowType::Popup);
 
-    m_list_view = m_list_window->set_main_widget<ListView>().release_value_but_fixme_should_propagate_errors();
+    m_list_view = m_list_window->set_main_widget<ListView>();
     m_list_view->set_should_hide_unnecessary_scrollbars(true);
     m_list_view->set_alternating_row_colors(false);
     m_list_view->set_hover_highlighting(true);