Modify AgentEnsembleTest and AgentHwTest teardown to check for warmbo…

…ot flag

Summary:
Currently, all of Agent Hw test relies on verifyAcrosswarmboots and so they dont worry about the TearDown implementation.

If any test relied on AgentHwTest or AgentEnsembleTest teardown, then they wont be able to support warmboot because it always exits in an non graceful manner.

Modify AgentEnsembleTest and AgentHwTest teardown to check for warmboot flag and pass in option to exit gracefully

Reviewed By: zechengh09

Differential Revision: D60946407

fbshipit-source-id: 2b4064a13ee403e2d8750c23252dc956acbdf394

fboss/agent/test/AgentEnsembleTest.cpp

@@ -65,7 +65,13 @@ void AgentEnsembleTest::TearDown() {
       (::testing::Test::HasFailure() && FLAGS_run_forever_on_failure)) {
     runForever();
   }
-  tearDownAgentEnsemble();
+  if (FLAGS_setup_for_warmboot &&
+      isSupportedOnAllAsics(HwAsic::Feature::WARMBOOT)) {
+    XLOG(DBG2) << "tearDownAgentEnsemble() for warmboot";
+    tearDownAgentEnsemble(true);
+  } else {
+    tearDownAgentEnsemble();
+  }
 }
 
 void AgentEnsembleTest::tearDownAgentEnsemble(bool doWarmboot) {