Changed busctl command for BMC dump

Signed-off-by: Anusha Dathatri <adathatr@in.ibm.com>
Change-Id: Ic4b777369379aab616297720c91d9bb1ed3d61f5
diff --git a/lib/dump_utils.robot b/lib/dump_utils.robot
index 81db023..5516f3f 100644
--- a/lib/dump_utils.robot
+++ b/lib/dump_utils.robot
@@ -264,7 +264,7 @@
     [Documentation]  Auto generate BMC dump.
 
     ${cmd}=  Catenate  busctl --verbose call xyz.openbmc_project.Dump.Manager
-    ...  /xyz/openbmc_project/dump/bmc xyz.openbmc_project.Dump.Create CreateDump a{ss} 0
+    ...  /xyz/openbmc_project/dump/bmc xyz.openbmc_project.Dump.Create CreateDump a{sv} 0
     ${stdout}  ${stderr}  ${rc}=
     ...  BMC Execute Command  ${cmd}
     [Return]  ${stdout}  ${stderr}  ${rc}