Update the VTS module according to the refactoring in aosp/2826571

Test: atest VtsAidlAuthGraphRoleTest, atest VtsAidlAuthGraphSessionTest
Change-Id: I6cc3bd17952f602b58668d35e09c6a5385c7de61
diff --git a/security/authgraph/default/src/fuzzer.rs b/security/authgraph/default/src/fuzzer.rs
index 6a9cfdd..d401777 100644
--- a/security/authgraph/default/src/fuzzer.rs
+++ b/security/authgraph/default/src/fuzzer.rs
@@ -25,7 +25,7 @@
 use std::sync::{Arc, Mutex};
 
 fuzz_target!(|data: &[u8]| {
-    let local_ta = LocalTa::new();
+    let local_ta = LocalTa::new().expect("Failed to create an AuthGraph local TA.");
     let service = AuthGraphService::new_as_binder(Arc::new(Mutex::new(local_ta)));
     fuzz_service(&mut service.as_binder(), data);
 });