Include robot assembly

[JesusSilvaUtrera]

🎉 New feature

Closes #237

Summary

I have added to the README.md of the andino_hardware package the assembly steps.

Test it

Just check the README.md

Checklist

• [ ] Signed all commits for DCO
• [ ] Added tests
• [ ] Added example and/or tutorial
• [ ] Updated documentation (as needed)

Note to maintainers: I will open the PR as a draft first to discuss what things to add, or whether the format is okay or not.

[JesusSilvaUtrera]

@francocipollone @jballoffet new PR to ease the review of the assembly process, PTAL so we can merge this part.