[FL-3098] Up toolchain to version 20 (#2397)

* Up toolchain to 20
* Python reformat, add version info into fbtenv

Co-authored-by: あく <alleteam@gmail.com>

scripts/flipper/assets/dolphin.py

@@ -22,7 +22,6 @@ def _convert_image(source_filename: str):
 
 
 class DolphinBubbleAnimation:
-
     FILE_TYPE = "Flipper Animation"
     FILE_VERSION = 1
 
@@ -243,7 +242,6 @@ class DolphinBubbleAnimation:
 
 
 class DolphinManifest:
-
     FILE_TYPE = "Flipper Animation Manifest"
     FILE_VERSION = 1