Multiple errors in sample transfer/streaming/streaming-02-kafka-to-http

[arekusutarakasiku]

Bug Report

Describe the Bug

Sample
transfer/streaming/streaming-02-kafka-to-http

Action

Start negotiate contract
curl -H 'Content-Type: application/json' -d @transfer/streaming/streaming-02-kafka-to-http/5-negotiate-contract.json -X POST "http://localhost:28181/management/v3/contractnegotiations" -s | jq [
Explanation
when trying to start negotiate contract with 5-negotiate-contract.json the returned json states that the multiple fields are missing or blank.

Expected Behavior

contract-negotiation-id in json will be returned

Observed Behavior

[
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/@type was expected to be http://www.w3.org/ns/odrl/2/Offer but it was not",
    "type": "ValidationFailure",
    "path": "https://w3id.org/edc/v0.0.1/ns/policy/@type",
    "invalidValue": [
      "https://w3id.org/edc/v0.0.1/ns/Offer"
    ]
  },
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/assigner/@id cannot be null or blank",
    "type": "ValidationFailure",
    "path": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/assigner/@id",
    "invalidValue": null
  },
  {
    "message": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/target/@id cannot be null or blank",
    "type": "ValidationFailure",
    "path": "https://w3id.org/edc/v0.0.1/ns/policy/http://www.w3.org/ns/odrl/2/target/@id",
    "invalidValue": null
  }

Steps to Reproduce

Steps to reproduce the behavior:
Follow
(https://github.com/eclipse-edc/Samples/tree/main/transfer/streaming/streaming-02-kafka-to-http)

Context Information

Used commit: 1d55b7c
OS: Ubuntu 24.04

Detailed Description

Same in https://github.com/eclipse-edc/Samples/tree/main/transfer/streaming/streaming-03-kafka-broker

Possible Implementation

[github-actions]

Thanks for your contribution 🔥 We will take a look asap 🚀

[ndr-brt]

this is somewhat related to what happened here: #334
because the test covering the samples are not using the same payloads as the samples themselves.
@arekusutarakasiku would you feel comfortable in contribute with a PR? (some inspiration can be drawn from here: #335)