feat(docs): Add Node setup instructions for nvm to contributing guide

- Added a detailed section on using Node Version Manager (nvm) to the contributing guide.
- The new section explains how contributors can ensure their Node.js version meets the project's requirements using `nvm`.
- Included instructions for installing `nvm`, switching Node versions, and installing specific versions if necessary.

This change aims to help contributors quickly set up their environment and avoid potential compatibility issues.

contributing.md

@@ -45,12 +45,25 @@ You would need [Node v20.x or the latest LTS version](https://nodejs.org/en/) an
 
 Bruno is being developed as a desktop app. You need to load the app by running the Next.js app in one terminal and then run the electron app in another terminal.
 
+### Setup Node
+
+   If your Node version does not meet the project's requirements as instructed by the docs, "nvm" (Node Version Manager) allows using Node at the version required by the project:
+
+   ```sh
+   nvm use
+   ```
+
+   You first might need to install the specific version:
+
+   ```sh
+   nvm install
+   ```
+
+   You can install nvm from [here](https://github.com/nvm-sh/nvm).
+
 ### Local Development
 
 ```bash
-# use nodejs 20 version
-nvm use
-
 # install deps
 npm i --legacy-peer-deps