fix(node): Update node tracing ESM imports. (#4876)

* fix(node): Update node tracing ESM imports.

* Update src/includes/getting-started-config/node.mdx

Co-authored-by: Katie Byers <[email protected]>

* Rename required variable in CJS example.

Co-authored-by: Katie Byers <[email protected]>

Author: onurtemizkan

src/includes/getting-started-config/node.mdx

@@ -4,7 +4,11 @@ Once this is done, Sentry's Node SDK captures all transactions and unhandled exc
 import * as Sentry from "@sentry/node";
 
 // Importing @sentry/tracing patches the global hub for tracing to work.
-import * as Tracing from "@sentry/tracing";
+import "@sentry/tracing";
+
+// If you want to use `@sentry/tracing` in your project directly, use a named import instead:
+// import * as SentryTracing from "@sentry/tracing"
+// Unused named imports are not guaranteed to patch the global hub.
 
 Sentry.init({
   dsn: "___PUBLIC_DSN___",
@@ -19,7 +23,7 @@ Sentry.init({
 const Sentry = require("@sentry/node");
 
 // Importing @sentry/tracing patches the global hub for tracing to work.
-const Tracing = require("@sentry/tracing");
+const SentryTracing = require("@sentry/tracing");
 
 Sentry.init({
   dsn: "___PUBLIC_DSN___",