Fix a regression in how required properties are collected.

+ Enable app standby mode before running the tests.

Fixes: 147459100
Fixes: 117169751
Test: atest hostsidetests/net/src/com/android/cts/net/HostsideRestrictBackgroundNetworkTests.java
Test: cts-tradefed run singleCommand cts-on-gsi --skip-device-info \
      --skip-preconditions -m CtsHostsideNetworkTests \
      -t com.android.cts.net.HostsideRestrictBackgroundNetworkTests

Change-Id: I782f8a06922622d28f9a9d5c9f2afa2b12f8aa80
diff --git a/tests/cts/hostside/AndroidTest.xml b/tests/cts/hostside/AndroidTest.xml
index 6ba6f42..0452fc6 100644
--- a/tests/cts/hostside/AndroidTest.xml
+++ b/tests/cts/hostside/AndroidTest.xml
@@ -20,6 +20,8 @@
     <option name="config-descriptor:metadata" key="parameter" value="not_multi_abi" />
     <option name="config-descriptor:metadata" key="parameter" value="secondary_user" />
 
+    <target_preparer class="com.android.cts.net.NetworkPolicyTestsPreparer" />
+
     <target_preparer class="com.android.tradefed.targetprep.RunCommandTargetPreparer">
         <option name="teardown-command" value="cmd power set-mode 0" />
         <option name="teardown-command" value="cmd battery reset" />