Adjust Preserve BMC Network Setting to handle boolean

The BMC code has switched from using "1" to using "True".

Change-Id: Id93672370c77483b7e0485d1e91985670bb3e64e
Signed-off-by: Michael Walsh <micwalsh@us.ibm.com>
diff --git a/extended/code_update/code_update_utils.robot b/extended/code_update/code_update_utils.robot
index 96f0378..906e943 100755
--- a/extended/code_update/code_update_utils.robot
+++ b/extended/code_update/code_update_utils.robot
@@ -23,8 +23,8 @@
     ${value}=    create dictionary   data=${policy}
     Write Attribute   ${BMC_UPD_ATTR}  preserve_network_settings  data=${value}
     ${data}=      Read Properties   ${BMC_UPD_ATTR}
-    should be equal as strings    ${data['preserve_network_settings']}   ${1}
-    ...   msg=0 indicates network is not preserved
+    Should Be Equal As Strings    ${data['preserve_network_settings']}   ${True}
+    ...   msg=False indicates network is not preserved.
 
 
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