Update Actions with Lychee and GitHub Token

[pderrenger]

This pull request adds an improved Ultralytics Actions workflow to automatically format code and documentation to the new Ultralytics official standards maintained at https://github.com/ultralytics/actions.

Five individual actions are run by default now including a new broken links check for markdown and HTML files. Disable individual actions by setting them to false or removing their line, i.e. delete 'markdown: true' line to disable markdown formatting.

To customize an action use a pyproject.toml file in this repo. For details see https://github.com/ultralytics/actions.

# Ultralytics 🚀 - AGPL-3.0 license
# Ultralytics Actions https://github.com/ultralytics/actions
# This workflow automatically formats code and documentation in PRs to official Ultralytics standards

name: Ultralytics Actions

on:
  push:
    branches: [main]
  pull_request_target:
    branches: [main]

jobs:
  format:
    runs-on: ubuntu-latest
    steps:
      - name: Run Ultralytics Formatting
        uses: ultralytics/actions@main
        with:
          token: ${{ secrets.GITHUB_TOKEN }}  # automatically generated
          python: true
          docstrings: true
          markdown: true
          spelling: true
          links: true

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Updated GitHub Actions and README.md in the Ultralytics Magellan project to streamline code quality and provide clearer documentation.

📊 Key Changes

• 🛠 Added a GitHub token to the formatting GitHub Action for authentication purposes.
• ✏️ Enabled various code quality checks like python formatting, docstring, markdown, and spelling checks but disabled link checks.
• 📝 Updated the README.md file to include a new badge for the Ultralytics Actions and improved the layout and presentation of the example code block.

🎯 Purpose & Impact

• The change in the GitHub Actions workflow ensures better code consistency and quality by running automated checks.
• Excluding link checks might reduce false positives during formatting checks.
• The badge in the README showcases the status of the repository's formatting checks, increasing transparency for users.
• Better formatted example code with clearer instructions in the README helps users get started with the Magellan software more easily.