Rename vts-core to vts

Bug: 151896491
Test: presubmit check
Exempt-From-Owner-Approval: This CL renames suite name vts-core to vts.
It won't change test logic or behavior.

Change-Id: If6cf4d005e2753ddb108885f41870d5466c16c50
diff --git a/Android.bp b/Android.bp
index ea81993..df49a01 100644
--- a/Android.bp
+++ b/Android.bp
@@ -119,6 +119,6 @@
     ],
     test_suites: [
         "device-tests",
-        "vts-core"
+        "vts"
     ],
 }