[cts] Fix ResourcesHardeningTest for secondary users Test used to install an app for the primary user only, but then tried to get its context for the current one, effectively breaking any runs as non-primary user. Bug: 197564905 Test: atest --user-type secondary_user ResourcesHardeningTest Change-Id: I81d0ee4214f1981d65788fd71a0801524cb60a0c