Merge "KeyMint VTS: catch empty cert chains" am: 38fe3c5962 am: 675972efc4 am: 9e1c4c1486 am: aed6d2b032

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1787827

Change-Id: I9d31e09f3d571c9da8cd038c5f512b08291e4dda