docs: add a next steps link to first page of migration docs

[miclgael]

On Discord, a user may have missed that there are next steps in the sidebar, adding a next steps link should help progress through the documentation.

Permalink: https://discord.com/channels/473401852243869706/473406004751499275/1100527969384017950

Screenshot:

🔗 Linked issue

N/A

❓ Type of change

• 📖 Documentation (updates to the documentation, readme or JSdoc annotations)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

• On Discord, I noticed that a user may have missed that there are next steps in the sidebar of this docs page
• Adding a next steps link should help to progress through the documentation.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

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[danielroe]

Thank you! ❤️