tcMatches can't deal with EmptyCase

Typechecking the following crashes the typechecker:

-- Should get the type: forall a1:Type. forall b1:Type. a1 -> b1
emptyCase x = case x of {}

Output of the test suite:

emptyCase-infer: FAIL
      [PprPanic]
      
      extractInferredResult
      Encountered a Hole!
      CallStack (from HasCallStack):
        pprPanic, called at src/Tc/Monad.hs:328:24 in typechecker-0.1.0.0-inplace:Tc.Monad