testsuite: add T25414 test case marked as broken

This commit adds T25414 test case to demonstrate #25414. It is marked
as broken and will be fixed by the next commit.

(cherry picked from commit b1eed26f)

testsuite/tests/ghci/scripts/T25414.script

+:set -XCApiFFI
+import Foreign
+import Foreign.C
+foreign import capi unsafe "stdlib.h malloc" c_malloc :: CSize -> IO (Ptr ())
+foreign import capi unsafe "stdlib.h free" c_free :: Ptr () -> IO ()
+c_free =<< c_malloc 16

testsuite/tests/ghci/scripts/all.T

@@ -360,6 +360,7 @@ test('T20455', normal, ghci_script, ['T20455.script'])
 test('shadow-bindings', normal, ghci_script, ['shadow-bindings.script'])
 test('T925', normal, ghci_script, ['T925.script'])
 test('T7388', normal, ghci_script, ['T7388.script'])
+test('T25414', [expect_broken(25414)], ghci_script, ['T25414.script'])
 test('T20627', normal, ghci_script, ['T20627.script'])
 test('T20473a', normal, ghci_script, ['T20473a.script'])
 test('T20473b', normal, ghci_script, ['T20473b.script'])