Only run MicrodroidTestApp.GTS on devices with SDK >= 34

The system apis were introduced in Android U (SDK level 34), however the
GTS tests are still run on Android T devices, hence skip the
MicrodroidTestApp.GTS there.

Bug: 394216351
Test: flash T build & run atest MicrodroidTestApp.GTS
Change-Id: I50bd5236d10fa2a73c758a89c0501997cb4f97fd
diff --git a/tests/testapk/Android.bp b/tests/testapk/Android.bp
index 806592d..e342f60 100644
--- a/tests/testapk/Android.bp
+++ b/tests/testapk/Android.bp
@@ -58,7 +58,8 @@
         // Non-VM payload libraries
         "libhwtrust_jni",
     ],
-    min_sdk_version: "33",
+    // AVF java APIs were introduced in Android U.
+    min_sdk_version: "34",
 }
 
 DATA = [