[lldb] Never disable the objc runtime for playgrounds

rdar://141447296

Author: augusto2112

lldb/source/Plugins/ExpressionParser/Swift/SwiftExpressionParser.cpp

@@ -812,6 +812,8 @@ SwiftExpressionParser::GetASTContext(DiagnosticManager &diagnostic_manager) {
     m_swift_ast_ctx.GetLanguageOptions().EnableTargetOSChecking = false;
 
     auto should_disable_objc_runtime = [&]() {
+      if (playground)
+        return false;
       lldb::StackFrameSP this_frame_sp(m_stack_frame_wp.lock());
       if (!this_frame_sp)
         return false;