Deskclock - set target sdk version to 30.

Made changes to Android.bp to match versions in AndroidManifest.xml

Bug: 209469462
Test: manual
Change-Id: I2ed5d940d52e080e553c001890bab7ccd6efc73e
diff --git a/Android.bp b/Android.bp
index d732f94..3c6477b 100644
--- a/Android.bp
+++ b/Android.bp
@@ -45,6 +45,7 @@
     ],
 
     sdk_version: "current",
+    target_sdk_version: "30",
     optimize: {
         proguard_flags_files: ["proguard.flags"],
     },