Remove UgBgGroupThrottle node to keep ug_bg_group_throttle 308 by default am: 3eb0dc523f am: 4c4b1c4a86

Original change: https://googleplex-android-review.googlesource.com/c/device/google/lynx/+/23672755

Change-Id: I46a15d4f4faeac3e6bfca34a0693569bdaebaa2f
Signed-off-by: Automerger Merge Worker <[email protected]>