Strip `adb devices` output for APK installs am: 1c982e13f1 am: 5f085877f9 am: ea116a00ce am: 700a05111e

Original change: https://android-review.googlesource.com/c/platform/tools/test/mobly_extensions/+/2545072

Change-Id: I8db9395f36ba785378d90533a66f684a59f50188
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/scripts/local_mobly_runner.py b/scripts/local_mobly_runner.py
index 9120f2f..b7e87ef 100755
--- a/scripts/local_mobly_runner.py
+++ b/scripts/local_mobly_runner.py
@@ -269,6 +269,7 @@
                 'adb devices | tail -n +2 | cut -f 1', shell=True
             )
             .decode('utf-8')
+            .strip()
             .splitlines()
         )
     for apk in apks: