Update vpnprofilestore_test to legacykeystore_test in TEST_MAPPING am: eeb6be2901 am: 4107fade78 am: a6f3625c20

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/cexpr/+/1756437

Change-Id: Ib929d79358a730c434450ccdefe2c4ffd8450212