cros kiosk: Speculatively enable ManagementApiKioskTest.ManagementApi

on branded builds

Bug: 977743
Change-Id: Ie0a017323f26051601bde74c4d28e41ea85a95df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2170866Reviewed-by: Roman Aleksandrov <raleksandrov@google.com>
Commit-Queue: Roman Sorokin [CET] <rsorokin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#763488}

testing/buildbot/filters/chromeos.browser_tests.filter

@@ -13,9 +13,6 @@
 # TODO(crbug.com/976083): Enable this.
 -MSE_Widevine/EncryptedMediaTest.*
 
-# TODO(crbug.com/977743): Enable this.
--ManagementApiKioskTest.ManagementApi
-
 # TODO(crbug.com/985390): Enable this.
 -OSSettingsPeoplePageAccountManagerTest.AllJsTests