Change binderRpcTest to use 'activity' for a Java test service

The service just needs to exist on all devices that this test runs on.
We recently hit an issue with 'batteryproperties' not existing. The
'activity' service is likely on more devices.

Test: atest binderRpcTest
Bug: 359783809
(cherry picked from https://android-review.googlesource.com/q/commit:29db860bfa17b7017de8464a262e7081b3b71112)
Merged-In: I71fea4daeb929971add9eefa96e3d48f815e2212
Change-Id: I71fea4daeb929971add9eefa96e3d48f815e2212

Author: devinmoore-goog

libs/binder/tests/binderRpcTest.cpp

@@ -1377,8 +1377,8 @@ TEST(BinderRpc, Java) {
     sp<IServiceManager> sm = defaultServiceManager();
     ASSERT_NE(nullptr, sm);
     // Any Java service with non-empty getInterfaceDescriptor() would do.
-    // Let's pick batteryproperties.
-    auto binder = sm->checkService(String16("batteryproperties"));
+    // Let's pick activity.
+    auto binder = sm->checkService(String16("activity"));
     ASSERT_NE(nullptr, binder);
     auto descriptor = binder->getInterfaceDescriptor();
     ASSERT_GE(descriptor.size(), 0u);