Fix lunch choices for git_main am: 26a6e0878b

Original change: https://android-review.googlesource.com/c/device/generic/uml/+/2811353

Change-Id: Ia46525079a7a0d8d8dedad4eae1c290a2909040e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>