fix(ci): update to new action inputs

The inputs changed a bit.

.forgejo/workflows/check.yml

@@ -39,6 +39,6 @@ jobs:
           # Generate artifacts on main (to speed up comparisons)
           generate-artifact: ${{ github.ref_name == 'main' }}
           # Generate comparisons to main
-          do-comparison: true
+          do-comparison: 'true'
           # This job's name (so we can find the artifacts)
           job-name: report-size