add preferred repository citation

[LucasLarson]

github.com/citation-file-format/ruby-cff:¹²

---
cff-version: 1.2.0
message: "Cite this software by using this metadata."
title: gunstage
abstract: |
  `gunstage` or `git unstage` is a command-line tool for unstaging files in a
  Git repository without the need to memorize the many ways Git recommends it
  be done and when.
authors:
  - given-names: Lucas
    family-names: Larson
    orcid: https://orcid.org/0000-0002-0317-5426
version: 1.7.0
date-released: 2022-03-29
license: GPL-3.0-or-later
url: https://github.com/LucasLarson/gunstage
repository-code: https://github.com/LucasLarson/gunstage

Footnotes

1. https://github.blog/?p=59229 ↩

2. YAML by any other name ↩