[#2082] Fix typo in command in Setting Up page

[supermii2]

Fixes #2082

Replace the command `npm -v` with `node -v`.
This displays the node version instead of the npm version.

[asdfghjkxd]

LGTM, node -v appears to show the installed node version!

[sopa301]

LGTM

[jonasongg]

Might want to change "Replaced" to "Replace" for the commit message!

[supermii2]

Might want to change "Replaced" to "Replace" for the commit message!

Edited! Thank you!

[ckcherry23]

Thanks @supermii2 for reporting and fixing this issue in the docs! Fixing such issues is very useful for future first-time contributors to get started easily.

[vvidday]

Nice catch!

Minor thing about the commit message body: try to follow the recommended format (more details)

{current situation} -- use present tense

{why it needs to change}

{what is being done about it} -- use imperative mood

{why it is done that way}

{any other relevant info}

Some parts might seem obvious/redundant especially for smaller changes, but it's good to develop the habit for future PRs. For example, the body could be:

Fix typo in Setting Up page

The command given in the developer guide for checking the local Node.js
version is `npm -v`, which displays the version of npm instead.

Let's replace the command with `node -v`, which correctly displays the
Node.js version.

[github-actions]

The following links are for previewing this pull request:

• Dashboard Preview: https://dashboard-2083-pr-reposense-reposense.surge.sh
• Docs Preview: https://docs-2083-pr-reposense-reposense.surge.sh