docs: fix .github/CONTRIBUTING.md formatting inconsistencies

[mulkymalikuldhrs]

Description

removed trailing whitespace on 3 line(s) in .github/CONTRIBUTING.md

Type of change

• Documentation improvement

Checklist

• I have read the CONTRIBUTING guide
• My changes follow the existing style

[github-actions]

👋 Hey there spelunker. It looks like you've modified some files that we can't accept as contributions:

• .github/CONTRIBUTING.md

You'll need to revert all of the files you changed that match that list using GitHub Desktop or git checkout origin/main <file name>. Once you get those files reverted, we can continue with the review process.

The complete list of files we can't accept are:

• .devcontainer/**
• .github/**
• data/reusables/rai/**
• Dockerfile*
• src/**
• package*.json
• content/actions/how-tos/security-for-github-actions/security-hardening-your-deployments/**

We also can't accept contributions to files in the content directory with frontmatter contentType: rai.

[github-actions]

How to review these changes 👓

Thank you for your contribution. To review these changes, choose one of the following options:

• Spin up a codespace
• Set up a local development environment

A Hubber will need to deploy your changes internally to review.

Table of review links

Note: Please update the URL for your staging server or codespace.

This pull request contains code changes, so we will not generate a table of review links.

🤖 This comment is automatically generated.