Fix lunch choices for git_main am: 644a59b607

Original change: https://android-review.googlesource.com/c/device/google/lynx/+/2811080

Change-Id: I344c3d50321d501266becdb7c675f2f2da3df587
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>