[sonic-cfggen]: Update test minigraph to fix interface (#9601)

Why I did it
Config db schema generated from test minigraph can't pass yang validation.

How I did it
Update test minigraph to fix interface

How to verify it
Build sonic-config-engine.
Run command 'sonic-cfggen -m xxx.xml --print-data', and check interface table and port table.

Signed-off-by: Gang Lv ganglv@microsoft.com

src/sonic-config-engine/tests/sample_graph.xml

@@ -111,7 +111,7 @@
       <DeviceLinkBase i:type="DeviceInterfaceLink">
         <Bandwidth>40000</Bandwidth>
         <ElementType>DeviceInterfaceLink</ElementType>
-        <EndDevice>OCPCH01040DDLF</EndDevice>
+        <EndDevice>OCPSCH01040DDLF</EndDevice>
         <EndPort>Ethernet1</EndPort>
         <StartDevice>OCPSCH0104002MS</StartDevice>
         <StartPort>Ethernet12</StartPort>