[security RP] mgmt, fix for java with directive (Azure#15169)

* [security] mgmt, fix for java with directive

* fix readme

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

@@ -0,0 +1,27 @@
+## Java
+
+These settings apply only when `--java` is specified on the command line.
+
+
+``` yaml $(java)
+directive:
+  - from: externalSecuritySolutions.json
+    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
+```

specification/security/resource-manager/readme.md

@@ -485,6 +485,7 @@ swagger-to-sdk:
   - repo: azure-sdk-for-python-track2
   - repo: azure-sdk-for-js
   - repo: azure-sdk-for-node
+  - repo: azure-sdk-for-java
   - repo: azure-resource-manager-schemas
 ```
 
@@ -512,4 +513,6 @@ See configuration in [readme.typescript.md](./readme.typescript.md)
 
 See configuration in [readme.ruby.md](./readme.ruby.md)
 
+## Java
 
+See configuration in [readme.java.md](./readme.java.md)