Update sdk_version in Android.bp to 23

AndroidManifest.xml specifies minSdkVersion 23, but the Android.bp
is compiling against SDK 21.  The new drop of ManifestMerger is
inserting an android:extractNativeLibs for minSdkVersion >= 23,
but that attribute is not defined in SDK 21.  Compile against
SDK 23 instead.

Test: m checkbuild
Change-Id: Ia8b2dbe2975891142406841032844d01106d9cfb
diff --git a/tests/jank/androidtvjanktests/Android.bp b/tests/jank/androidtvjanktests/Android.bp
index 0c74b4a..45e303e 100644
--- a/tests/jank/androidtvjanktests/Android.bp
+++ b/tests/jank/androidtvjanktests/Android.bp
@@ -23,7 +23,7 @@
         "dpad-util",
     ],
 
-    sdk_version: "21",
+    sdk_version: "23",
 
     test_suites: ["device-tests"],
 }