mgmt, security PR, improve directive to avoid hardcode the properties (#15220)

Author: weidongxu-microsoft

specification/security/resource-manager/readme.java.md

@@ -9,19 +9,8 @@ directive:
     where: $.definitions.ExternalSecuritySolution.allOf[1]
     set:
       type: object
-      description: 'Describes an Azure resource with location'
     reason: discriminator property is required to be defined in the model
   - from: externalSecuritySolutions.json
-    where: $.definitions.ExternalSecuritySolution.properties
-    set:
-      kind:
-        type: object
-        description: 'Describes an Azure resource with kind'
-        enum:
-          - CEF
-          - ATA
-          - AAD
-        x-ms-enum:
-          name: ExternalSecuritySolutionKind
-          modelAsString: true
+    where: $.definitions
+    transform: $.ExternalSecuritySolution.properties = $.ExternalSecuritySolutionKind.properties
 ```