Enhance BubbleController dumps

- Fix a formatting issue
- Dump Bubble$mIsClearable in BubblesController
  Sometimes when dismissing a Notification which has a Bubble, it gets stuck in the Shade. A possible reason is that we restore the wrong value for this field (false), which blocks us from dismissing it.

Bug: 237897866
Test: adb shell dumpsys activity service com.android.systemui/.SystemUIService WMShell
Change-Id: I38fc1355b4706cab3cf87f415e97f569e2e2ba50