Docs: Adds 2 references to the node.js versions we use for v3 and v4 (#2118)

* Adds 2 snippets to reference node.js version for v3 and v4

* Updated the node versions we support

* Remove specific node version from title

Author: samejr

docs/config/config-file.mdx

@@ -6,6 +6,7 @@ description: "This file is used to configure your project and how it's built."
 
 import ScrapingWarning from "/snippets/web-scraping-warning.mdx";
 import BundlePackages from "/snippets/bundle-packages.mdx";
+import NodeVersions from "/snippets/node-versions.mdx";
 
 The `trigger.config.ts` file is used to configure your Trigger.dev project. It is a TypeScript file at the root of your project that exports a default configuration object. Here's an example:
 
@@ -245,6 +246,10 @@ export default defineConfig({
 
 See our [Bun guide](/guides/frameworks/bun) for more information.
 
+### Node.js versions
+
+<NodeVersions />
+
 ## Default machine
 
 You can specify the default machine for all tasks in your project:

docs/snippets/node-versions.mdx

@@ -0,0 +1,4 @@
+Trigger.dev runs your tasks on specific Node.js versions:
+
+- **v3**: Uses Node.js `21.7.3`
+- **v4**: Uses Node.js `21.7.3` 

docs/upgrade-to-v4.mdx

@@ -3,10 +3,16 @@ title: "Upgrading to v4"
 description: "What's new in v4, how to upgrade, and breaking changes."
 ---
 
+import NodeVersions from "/snippets/node-versions.mdx";
+
 ## What's new in v4?
 
 [Read our blog post](https://trigger.dev/blog/v4-beta-launch) for an overview of the new features.
 
+### Node.js support
+
+<NodeVersions />
+
 ### Wait tokens
 
 In addition to waiting for a specific duration, or waiting for a child task to complete, you can now create and wait for a token to be completed, giving you more flexibility and the ability to wait for arbitrary conditions. For example, you can send the token to a Slack channel, and only complete the token when the user has clicked an "Approve" button.