Do not fail the test on non-zero exit code from stacklight-pytest

Change-Id: I4b97735b5892df07d6c30f04b1013132581df6fd
diff --git a/tcp_tests/managers/sl_manager.py b/tcp_tests/managers/sl_manager.py
index 68ff0de..142cd3f 100644
--- a/tcp_tests/managers/sl_manager.py
+++ b/tcp_tests/managers/sl_manager.py
@@ -105,7 +105,7 @@
                 as node_remote:
             LOG.debug("Run {0} on the node {1}".format(
                 cmd, target_node_name[0]))
-            result = node_remote.check_call(cmd, verbose=True)
+            result = node_remote.execute(cmd, verbose=True)
             LOG.debug("Test execution result is {}".format(result))
         return result
 
@@ -127,7 +127,7 @@
                 as node_remote:
             LOG.debug("Run {0} on the node {1}".format(
                 cmd, target_node_name[0]))
-            node_remote.check_call(cmd, verbose=True)
+            node_remote.execute(cmd, verbose=True)
             res = node_remote.check_call('cd {0}; cat report.json'.format(
                 tests_path), verbose=True)
             LOG.debug("Test execution result is {}".format(res['stdout']))