inspector: use const for contextGroupId

PR-URL: #29076
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>

src/inspector_agent.cc

@@ -232,7 +232,7 @@ class ChannelImpl final : public v8_inspector::V8Inspector::Channel,
                        bool prevent_shutdown)
       : delegate_(std::move(delegate)), prevent_shutdown_(prevent_shutdown),
         retaining_context_(false) {
-    session_ = inspector->connect(1, this, StringView());
+    session_ = inspector->connect(CONTEXT_GROUP_ID, this, StringView());
     node_dispatcher_ = std::make_unique<protocol::UberDispatcher>(this);
     tracing_agent_ =
         std::make_unique<protocol::TracingAgent>(env, main_thread_);