Add a testcase for #13227

where an expected float-out is not happening.

testsuite/tests/simplCore/should_run/T13227.hs

+import Debug.Trace
+
+g x expensive ys = let h = \y -> y + expensive x
+                   in map h ys
+{-# NOINLINE g #-}
+
+foo x = trace "Evaluate me only once!" x
+
+main = sum (g 1 foo [1,2,3]) `seq` return ()
+

testsuite/tests/simplCore/should_run/T13227.stderr

+Evaluate me only once!

testsuite/tests/simplCore/should_run/all.T

@@ -73,3 +73,4 @@ test('T12689broken', expect_broken(12689), compile_and_run, [''])
 test('T12689a', normal, compile_and_run, [''])
 
 test('T13172', only_ways(['optasm']), compile_and_run, ['-dcore-lint'])
+test('T13227', expect_broken(13227), compile_and_run, [''])