Bump fsfe/reuse-action from 3 to 4 (#780)

Bumps [fsfe/reuse-action](https://github.com/fsfe/reuse-action) from 3 to 4.
- [Release notes](https://github.com/fsfe/reuse-action/releases)
- [Commits](https://github.com/fsfe/reuse-action/compare/v3...v4)

---
updated-dependencies:
- dependency-name: fsfe/reuse-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/reuse.yml

@@ -29,4 +29,4 @@ jobs:
           rm -f tests/integration/targets/*/files/roots/*.pem
 
       - name: REUSE Compliance Check
-        uses: fsfe/reuse-action@v3
+        uses: fsfe/reuse-action@v4