Upgrade robolectric to /external/robolectric to prep for removal of /external/robolectric shadows. am: 9e34a097be

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/KeyChain/+/21778940

Change-Id: Ia6c1cdb22b5a73fc526c7d12a061f43b9769da36
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>