Latest in fuchsia flashing changed to look at second latest build

There is a possible issue where the latest uploaded build is not
complete when the flashing script tries to pull the build down,
which results in a partial build being pulled down and flashing
to fail.  By changing it to the second most latest, the build
is guaranteed to be fully uploaded when flashing is called.

Bug: None
Test: Verified build is still pulled down correctly.
Change-Id: I2c69f94eed5ebb9bd5f14dcf7ad5a1ba1426ac82
diff --git a/acts/framework/acts/controllers/fuchsia_lib/utils_lib.py b/acts/framework/acts/controllers/fuchsia_lib/utils_lib.py
index 9e2e326..306d9d2 100644
--- a/acts/framework/acts/controllers/fuchsia_lib/utils_lib.py
+++ b/acts/framework/acts/controllers/fuchsia_lib/utils_lib.py
@@ -262,7 +262,7 @@
             elif fuchsia_device.build_number == 'LATEST':
                 build_list = [x for x in build_list if '.' in x]
             if build_list:
-                fuchsia_device.build_number = build_list[-1]
+                fuchsia_device.build_number = build_list[-2]
             else:
                 raise FileNotFoundError('No build(%s) on the found on %s.' % (
                     fuchsia_device.build_number, fuchsia_device.server_path))