Update azure static web app task output variables

[kwickramasekara]

It looks like the Azure Static Web Apps task has an output variable (AZURESTATICWEBAPP_STATIC_WEB_APP_URL) which however is not documented in the docs.

P.S: I know this section might be auto generated, so I don't anticipate this PR being merged. But I wanted to bring this to attention since this can be particularly useful as static web apps generate random URLs for preview environments.

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[steved0x]

@kwickramasekara Thank you for submitting this PR. Unfortunately, it would get overwritten the next time the tooling is run, because that part of the article is autogenerated (as you noted in your comment) from the task source code. Here is an example of another task that has an output variable:
https://github.com/microsoft/azure-pipelines-tasks/blob/111fe5c599d29e24d4dc487b0551fd83891a9c56/Tasks/AzureFileCopyV6/task.json#L205

  "outputVariables": [
    {
      "name": "StorageContainerUri",
      "description": "Uri of the container where the files were copied to. Valid only when the selected destination is Azure Blob."
    }

Which surfaces in the docs like this:
https://learn.microsoft.com/en-us/azure/devops/pipelines/tasks/reference/azure-file-copy-v6?view=azure-pipelines#output-variables

Let me do some research on this and see if I can get that output variable added to the task metadata for the Static Web App task, and then it will automatically show up in the task documentation. In the meantime, I can add a note in the remarks for that task. I'll keep this PR open until I can make that change.

Update: I have created a PR in the tasks repo to add this variable. When it is merged there, it will automatically reflect in the task article. I will add remarks to emphasize this for Azure DevOps Server 2022 customers, because this change won't get reflected there except in the latest updates.
microsoft/azure-pipelines-tasks#20009

[kwickramasekara]

@steved0x sounds good, thank you for sharing that info.