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:376afa3cd8ee16dd15f597dbe4de6fea297ab6ad)
Merged-In: Ide29a6e31d1a07d7d395919cabee997dc3520ffc
Change-Id: Ide29a6e31d1a07d7d395919cabee997dc3520ffc
1 file changed