[JavaJaxRs] enumClass.mustache added getValue()

JavaJaxRs enums are missing getValue() method returning the correct data type.

Author: eric-rolli

modules/openapi-generator/src/main/resources/JavaJaxRS/enumClass.mustache

@@ -36,8 +36,12 @@
       this.value = value;
     }
 
-    @Override
     @JsonValue
+    public {{{dataType}}} getValue() {
+      return value;
+    }
+
+    @Override
     public String toString() {
       return String.valueOf(value);
     }