Fix: Only create @babel/node IPC channel when needed (#13295)

Co-authored-by: Huáng Jùnliàng <jlhwung@gmail.com>

packages/babel-node/test/fixtures/cli/subprocess-ipc/in-files/payload.js

@@ -1,2 +1,2 @@
 process.send({ hello: "world" });
-console.log("sent");
+console.log("ipc enabled");

packages/babel-node/test/fixtures/cli/subprocess-ipc/options.json

@@ -0,0 +1,6 @@
+{
+  "args": ["payload.js"],
+  "ipcMessage": { "hello": "world" },
+  "ipc": true,
+  "stdout": "ipc enabled"
+}

packages/babel-node/test/fixtures/cli/subprocess-no-ipc/in-files/payload.js

@@ -0,0 +1,3 @@
+if (process.send == null) {
+    console.log("ipc disabled");
+}

packages/babel-node/test/fixtures/cli/subprocess-no-ipc/options.json

@@ -1,4 +1,4 @@
 {
   "args": ["payload.js"],
-  "stdout": "sent"
+  "stdout": "ipc disabled"
 }

packages/babel-node/test/fixtures/misc/child.js

@@ -1 +0,0 @@
-process.send("hello");