Update vpnprofilestore_test to legacykeystore_test in TEST_MAPPING

The test had been changed to legacykeystore_test from ag/14968529

Bug: 192796637
Test: presubmit
Change-Id: Ifeca2f0675c647e78eec5c95d02d9783f752c776
diff --git a/TEST_MAPPING b/TEST_MAPPING
index a60a6e8..292b6c2 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -5,7 +5,7 @@
       "name": "keystore2_test"
     },
     {
-      "name": "vpnprofilestore_test"
+      "name": "legacykeystore_test"
     },
     {
       "name": "libsqlite3-sys_device_test_src_lib"