test: add promises metadata to postmortem test

type_JSPromise__JS_PROMISE_TYPE and
type_JSMessageObject__JS_MESSAGE_OBJECT_TYPE will be used on llnode to
identify Promises in memory and core dumps:
nodejs/llnode#272. Add these to our postmortem
test so we're aware of any changes to this metadata.

PR-URL: #31357
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

test/v8-updates/test-postmortem-metadata.js

@@ -161,7 +161,9 @@ function getExpectedSymbols() {
     'v8dbg_type_JSFunction__JS_FUNCTION_TYPE',
     'v8dbg_type_JSGlobalObject__JS_GLOBAL_OBJECT_TYPE',
     'v8dbg_type_JSGlobalProxy__JS_GLOBAL_PROXY_TYPE',
+    'v8dbg_type_JSMessageObject__JS_MESSAGE_OBJECT_TYPE',
     'v8dbg_type_JSObject__JS_OBJECT_TYPE',
+    'v8dbg_type_JSPromise__JS_PROMISE_TYPE',
     'v8dbg_type_JSRegExp__JS_REG_EXP_TYPE',
     'v8dbg_type_JSTypedArray__JS_TYPED_ARRAY_TYPE',
     'v8dbg_type_Map__MAP_TYPE',