chore: bump version to 3.9.0+115, add new translators

- Bump app version from 3.8.8 to 3.9.0 (build 115)
- Add 4 new Crowdin translators: unkn0wn (Indonesian), lunching1272
  (Chinese Simplified), Сергей Ильченко (Russian), Girl-lass (Chinese
  Simplified)

pubspec.yaml

@@ -1,7 +1,7 @@
 name: spotiflac_android
 description: Download Spotify tracks in FLAC from Tidal, Qobuz & Deezer
 publish_to: "none"
-version: 3.8.8+114
+version: 3.9.0+115
 
 environment:
   sdk: ^3.10.0