fix: add alternate default for network input of instance_template (#466)

Co-authored-by: abhishek kumar tiwari <[email protected]>

Author: amrkk123

modules/instance_template/metadata.display.yaml

@@ -120,6 +120,9 @@ spec:
         network:
           name: network
           title: Network
+          altDefaults:
+            - type: ALTERNATE_TYPE_DC
+              value: default
         network_ip:
           name: network_ip
           title: Network Ip