chore(example): Improve nullability docs (#1486)

Co-authored-by: sam0r040 <[email protected]>

Author: timonback

springwolf-examples/springwolf-kafka-example/src/main/java/io/github/springwolf/examples/kafka/dtos/RequiredAndNullablePayloadDto.java

@@ -10,7 +10,7 @@
 import static io.swagger.v3.oas.annotations.media.Schema.RequiredMode.NOT_REQUIRED;
 import static io.swagger.v3.oas.annotations.media.Schema.RequiredMode.REQUIRED;
 
-@Schema(description = "Another payload model")
+@Schema(description = "Demonstrate required and nullable. Note, @Schema is only descriptive without nullability check")
 @Data
 @AllArgsConstructor
 @NoArgsConstructor

springwolf-examples/springwolf-kafka-example/src/test/resources/asyncapi.json

@@ -1309,7 +1309,7 @@
             "description": "This field must be present, and value cannot be null"
           }
         },
-        "description": "Another payload model",
+        "description": "Demonstrate required and nullable. Note, @Schema is only descriptive without nullability check",
         "examples": [
           {
             "enumField": "COMPLEX1",
@@ -1326,7 +1326,7 @@
         ],
         "x-json-schema": {
           "$schema": "https://json-schema.org/draft-04/schema#",
-          "description": "Another payload model",
+          "description": "Demonstrate required and nullable. Note, @Schema is only descriptive without nullability check",
           "properties": {
             "enumField": {
               "description": "Follows OpenAPI 3.1 spec",

springwolf-examples/springwolf-kafka-example/src/test/resources/asyncapi.yaml

@@ -958,7 +958,8 @@ components:
         requiredField:
           type: string
           description: "This field must be present, and value cannot be null"
-      description: Another payload model
+      description: "Demonstrate required and nullable. Note, @Schema is only descriptive\
+        \ without nullability check"
       examples:
         - enumField: COMPLEX1
           notRequiredField: string
@@ -971,7 +972,8 @@ components:
         - requiredField
       x-json-schema:
         $schema: https://json-schema.org/draft-04/schema#
-        description: Another payload model
+        description: "Demonstrate required and nullable. Note, @Schema is only descriptive\
+          \ without nullability check"
         properties:
           enumField:
             description: Follows OpenAPI 3.1 spec