ci: revert artifact up- and download action to v3

(cherry picked from commit c819704b49)

.gitea/workflows/release.yml

@@ -28,7 +28,7 @@ jobs:
           nix-shell --run ./run-ci.sh
       - name: Upload artifact
         id: artifact-upload
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v3
         with:
           name: example-document
           path: ${{ github.workspace }}/example.pdf
@@ -51,7 +51,7 @@ jobs:
           go-version: '>=1.20.1'
       - name: Download Artifact
         id: download
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v3
         with:
           name: example-document
           path: ${{ github.workspace }}/Example.pdf