[PSM Interop] Change the log message from Client pods to Client container (#34029)

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tools/run_tests/xds_k8s_test_driver/framework/xds_k8s_testcase.py

@@ -670,7 +670,7 @@ class IsolatedXdsKubernetesTestCase(
                 client_restarts,
                 0,
                 msg=(
-                    "Client pods unexpectedly restarted"
+                    "Client container unexpectedly restarted"
                     f" {client_restarts} times during test. In most cases, this"
                     " is caused by the test client app crash."
                 ),
@@ -679,7 +679,7 @@ class IsolatedXdsKubernetesTestCase(
                 server_restarts,
                 0,
                 msg=(
-                    "Server pods unexpectedly restarted"
+                    "Server container unexpectedly restarted"
                     f" {server_restarts} times during test. In most cases, this"
                     " is caused by the test client app crash."
                 ),

tools/run_tests/xds_k8s_test_driver/framework/xds_url_map_testcase.py

@@ -436,7 +436,7 @@ class XdsUrlMapTestCase(absltest.TestCase, metaclass=_MetaXdsUrlMapTestCase):
 
             # Fail if any of the pods restarted.
             error_msg = (
-                "Client pods unexpectedly restarted"
+                "Client container unexpectedly restarted"
                 f" {client_restarts} times during test."
                 " In most cases, this is caused by the test client app crash."
             )