Separate jobs run in separate contexts.

I thought that workflows were isolated but jobs were not. Ah well.

.github/workflows/doc.yaml

@@ -13,10 +13,6 @@ jobs:
       - name: Build documentation
         run: |
           earthly --ci --output +doc
-  upload:
-    needs: build
-    runs-on: ubuntu-22.04
-    steps:
       - name: Upload build for GitHub Pages
         uses: actions/upload-pages-artifact@v3
         with:
@@ -29,7 +25,7 @@ jobs:
     environment:
       name: github-pages
       url: ${{ steps.deployment.outputs.page_url }}
-    needs: upload
+    needs: build
     runs-on: ubuntu-22.04
     steps:
       - name: Deploy to GitHub Pages