Merge pull request rails#51736 from maniSHarma7575/51689-remove-warning-from-render-test

[FIX] Remove warning for frozen string literal from the render test for action view

Author: yahonda

actionview/test/template/render_test.rb

@@ -793,7 +793,7 @@ def test_render_object
   end
 
   def test_render_mutate_string_literal
-    assert_equal "foobar", @view.render(inline: "'foo' << 'bar'", type: :ruby)
+    assert_equal "foobar", @view.render(inline: "+'foo' << 'bar'", type: :ruby)
   end
 end