Migrate packages/inputmethods/LatinIME to androidx.test

See go/jetpack-test-android-migration

Test: make checkbuild
Change-Id: I63edeced1465725cd8d6467cd75ea1acc2608932
diff --git a/tests/AndroidManifest.xml b/tests/AndroidManifest.xml
index 125aa10..e788e0b 100644
--- a/tests/AndroidManifest.xml
+++ b/tests/AndroidManifest.xml
@@ -28,7 +28,7 @@
         <!-- meta-data android:name="com.android.contacts.iconset" android:resource="@xml/iconset" /-->
     </application>
 
-    <instrumentation android:name="android.support.test.runner.AndroidJUnitRunner"
+    <instrumentation android:name="androidx.test.runner.AndroidJUnitRunner"
         android:targetPackage="com.android.inputmethod.latin"
         android:label="LatinIME tests">
     </instrumentation>