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: I2dcfd3e283e452086a75ea6fb8e61c8f0250dc2a
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 5958510..f5ee272 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -59,7 +59,7 @@
       "name": "logger_device_unit_tests"
     },
     {
-      "name": "vpnprofilestore_test"
+      "name": "legacykeystore_test"
     }
   ]
 }