testsuite: add regression test T25473

This commit adds regression test T25473 marked as broken due to #25473.
It will be fixed in the subsequent commit.

(cherry picked from commit ed2ed6c5)

testsuite/tests/th/wasm/T25473A.hs

+module T25473A where
+
+import GHC.Wasm.Prim
+
+type BinOp a = a -> a -> a
+
+foreign import javascript "wrapper"
+  mkJSBinOp :: BinOp Int -> IO JSVal

testsuite/tests/th/wasm/T25473B.hs

+{-# LANGUAGE TemplateHaskell #-}
+
+module T25473B where
+
+import Language.Haskell.TH
+import T25473A
+
+$(runIO $ do
+  _ <- mkJSBinOp (+)
+  pure [])

testsuite/tests/th/wasm/all.T

+setTestOpts([
+  unless(arch('wasm32'), skip)
+])
+
+test('T25473', [expect_broken(25473)], multimod_compile, ['T25473B', '-v0'])