Shim environment variables from CI

.gitea/workflows/ci.yml

@@ -14,7 +14,9 @@ jobs:
           python-version: "3.11"
       - name: Install dependencies
         run: pip install -r requirements.txt
-      - run: env
+      - run: |
+          export GITEA_TOKEN=$GITHUB_TOKEN
+          export GITEA_URL=$GITHUB_SERVER_URL
       - name: Build
         run: ./resize.py
       - name: Upload