Clarify details in PipelineExecutionStepState

[kwin]

The details element in

cloudmanager-api-docs/swagger-specs/api.yaml

Line 1707 in b6c0678

details:

does not define which map keys to expect there.

I have seen the following details map

      "environmentUrls": [
          {
            "instanceType": "author",
            "instanceUrl": "https://author-p7802-e44859.adobeaemcloud.com"
          },
          {
            "instanceType": "publish",
            "instanceUrl": "https://publish-p7802-e44859.adobeaemcloud.com"
          }
        ],
        "deploymentStepDescription": "[{\"id\":1,\"stepAction\":\"update-author-indexes\",\"updated\":\"2020-11-02T13:24:11.870+0000\"},{\"id\":2,\"stepAction\":\"update-publish-indexes\",\"updated\":\"2020-11-02T13:27:22.581+0000\"},{\"id\":3,\"stepAction\":\"update-services\",\"updated\":\"2020-11-02T13:27:46.629+0000\"},{\"id\":4,\"stepAction\":\"install-mutable-content\",\"updated\":\"2020-11-02T13:37:18.741+0000\"}]"

Would be nice to clarify this in a model or at least in some accompanying markdown document.