Unbind Attestation keys when freeing up namespace. am: d337c77271 am: 2feb0d0801

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/security/+/18638770

Change-Id: I2c3cde2a21a62f08d18ef25102de037851dc17d0
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>