[sil-verifier] Use the scope result rather than the scope instruction when verifying that we end scope instructions.

We do this since we need to be able to handle instructions that may have two
different results that independently need their scopes lifetime to be ended.

test/SIL/verifier_failures.sil

@@ -89,3 +89,18 @@ failure(%error : @owned $any Error):
   dealloc_stack %allocation : $*Builtin.SILToken
   throw %error : $any Error
 }
+
+sil [ossa] @yield_test : $@yield_once @convention(thin) (@inout Builtin.Int32) -> @yields @inout Builtin.Int32 {
+bb0(%0 : $*Builtin.Int32):
+  (%2, %3) = begin_apply undef(%0) : $@yield_once @convention(method) (@inout Builtin.Int32) -> @yields @inout Builtin.Int32
+  yield %2, resume bb1, unwind bb2
+
+bb1:
+  %5 = end_apply %3 as $()
+  %6 = tuple ()
+  return %6
+
+bb2:
+  abort_apply %3
+  unwind
+}