Remove user TIS unlocked runnable when a TIS instance is destroyed

- If the TIS instance is destroyed, then we should remove any queued
  user-unlocked runnables to ensure that they do not attempt to run
  again

Flag: EXEMPT bugfix
Bug: 373671447
Test: atest NexusLauncherTests
Change-Id: I8ca3cdfa6f849bce5d347f14038e1ebd6bc6ff06