chore: downgrade reuse to 5.1.1

reuse 6.y.z start require us to write `REUSE-IgnoreStart` everywhere, which cannot be done in some markdown files. Temporary switch back to 5.y.z for now.

Author: BLumia

.github/workflows/license-check.yml

@@ -19,7 +19,7 @@ jobs:
 
       - name: Run REUSE lint
         id: lcheck
-        run: pipx run reuse==6.2.0 lint
+        run: pipx run reuse==5.1.1 lint
         continue-on-error: true
         env:
           PIPX_DEFAULT_PYTHON: ${{ steps.python.outputs.python-path }}