Fix lunch choices for git_main

We add "trunk_staging-" for all COMMON_LUNCH_CHOICES so they are
valid in the trunk stable setup.

Bug: 307738446
Test: lunch
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:c0159563f3835c858d6587bebcbd87d123113530)
Merged-In: I47590aaf84bd2481d53c04889c2963e02b7a816d
Change-Id: I47590aaf84bd2481d53c04889c2963e02b7a816d
1 file changed