Change test type from InstrumentationTest to AndroidJUnitTest

Details about test configs changes are tracked in doc
https://docs.google.com/document/d/1EWUjJ7fjy8ge_Nk0YQbFdRp8DSHo3z6GU0R8jLgrAcw/edit#

Bug: 35882476
Test: local test
Change-Id: Ib403ce00ed33de3a39534f84da2a679f244e7a1c
diff --git a/tests/unit/AndroidTest.xml b/tests/unit/AndroidTest.xml
index 80a5a73..b74c1e3 100644
--- a/tests/unit/AndroidTest.xml
+++ b/tests/unit/AndroidTest.xml
@@ -20,7 +20,7 @@
 
     <option name="test-suite-tag" value="apct" />
     <option name="test-tag" value="SettingsUnitTests" />
-    <test class="com.android.tradefed.testtype.InstrumentationTest" >
+    <test class="com.android.tradefed.testtype.AndroidJUnitTest" >
         <option name="package" value="com.android.settings.tests.unit" />
         <option name="runner" value="android.support.test.runner.AndroidJUnitRunner" />
     </test>