shill: cellular: Update additiona_providers uuids to standard format.

After CL:198774 we use standard 128 bit uuids. This CL updates the additional
manually maintained providers to follow suit.

As a result, it updates the references to Verizon Wirless uuids in the cellular
code.

BUG=chromium:371179
TEST=Run shill_unittests.
     Test verizon LTE activation.

Change-Id: Ic70ec4d7c04364f5790562b2a8d9ac2630a2c964
Reviewed-on: https://chromium-review.googlesource.com/198794
Reviewed-by: Ben Chan <benchan@chromium.org>
Commit-Queue: Prathmesh Prabhu <pprabhu@chromium.org>
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>