chore: generate ffmpeg zip on linux release

.circleci/config.yml

@@ -427,6 +427,10 @@ steps-electron-build-for-publish: &steps-electron-build-for-publish
     # Node.js headers
     - *step-nodejs-headers-build
 
+    # ffmpeg
+    - *step-ffmpeg-gn-gen
+    - *step-ffmpeg-build
+
     # Publish
     - *step-electron-publish