Update reuse requirement from ~=5.1.1 to ~=6.1.2 (#62)

Updates the requirements on [reuse](https://github.com/fsfe/reuse-tool) to permit the latest version.
- [Release notes](https://github.com/fsfe/reuse-tool/releases)
- [Changelog](https://github.com/fsfe/reuse-tool/blob/main/CHANGELOG.md)
- [Commits](fsfe/reuse-tool@v5.1.1...v6.1.2)

---
updated-dependencies:
- dependency-name: reuse
  dependency-version: 6.1.2
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -3,7 +3,7 @@
 
 Sphinx~=8.2
 doc8~=2.0.0
-reuse~=5.1.1
+reuse~=6.1.2
 sphinx-rtd-theme~=3.0.2
 sphinxcontrib-spelling~=8.0.1
 sphinx-multiversion~=0.2.4