DevTools: Use default constructors/destructors

https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#cother-other-default-operation-rules

"The compiler is more likely to get the default semantics right and
you cannot implement these functions better than the compiler."

Userland/DevTools/HackStudio/Dialogs/NewProjectDialog.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2021, Nick Vella <nick@nxk.io>
+ * Copyright (c) 2022, the SerenityOS developers.
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -101,10 +102,6 @@ NewProjectDialog::NewProjectDialog(GUI::Window* parent)
     };
 }
 
-NewProjectDialog::~NewProjectDialog()
-{
-}
-
 RefPtr<ProjectTemplate> NewProjectDialog::selected_template()
 {
     if (m_icon_view->selection().is_empty()) {