Enable lockscreen shortcuts when hub V2 flag is enabled

We will flag off enabling the custom_lockscreen_shortcuts_enabled for
future launches. However, that requires a read only flag which doesn't
support teamfooding, so until trunkfood entry, we'll need to rely on
the hub v2 flag to enable lockscreen shortcuts.

Bug: 380335989
Bug: 383391342
Test: atest KeyguardQuickAffordanceLocalUserSelectionManagerTest
      also manually verified on device with flag flips
Flag: com.android.systemui.glanceable_hub_v2
Change-Id: I95e16a6bbaa5cb86fa3097e4d3602fc2363f18c7