Remove unnecessary cp step in draft-pdf workflow

inara CDs into the paper/ directory before running pandoc, so images
in paper/ are already on the resource path. No copying needed.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: TomeHirata

.github/workflows/draft-pdf.yml

@@ -10,8 +10,6 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5  # v4
-      - name: Copy figures to repo root for inara
-        run: cp paper/*.png .
       - name: Build draft PDF
         uses: openjournals/openjournals-draft-action@85a18372e48f551d8af9ddb7a747de685fbbb01c  # master
         with: