gfxstream-protocols: use bash instead of shell script am: 294d7397ff

Original change: https://android-review.googlesource.com/c/platform/external/gfxstream-protocols/+/2260367

Change-Id: I658b0e06746c680f2b1069bab019480041220ef8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>