Add another integration, fix whitespace around punctuation

[astro]

Reason for this PR

Except in French, there is no whitespace preceding punctuation marks.

Description of changes

Links to a project that makes it easy to run NixOS VMs on Firecracker.

License acceptance

By submitting this pull request, I confirm that my contribution is made under
the terms of the MIT-0 [1] license.

[1] https://github.com/aws/mit-0

PR checklist

[Author TODO: Meet these criteria & check the boxes.]
[Reviewer TODO: Verify checked boxes. Request changes if criteria not met]

• The reason for this PR is clearly provided (issue no. or explanation).
• The description of changes is clear and encompassing.
• All commits in this PR are signed (git commit -s).

[xmarcalx]

Hi @astro,

Thank you very much for the changes and welcome to Firecracker community.
I left some minor comments. Would you be ok for you to address them?

[xmarcalx]

Thanks for resolving the issues!