Azure-devops-docs: checkout clean settings are wrong

[AArnott]

Under the checkout: self step, the clean property must be true to clean. The all | outputs | resources value is ignored and causes git checkout to _not_ clean at all.
An AZP engineer told me that the all | outputs | resources setting only applies to cleaning of workspaces.

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Document Details

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• ID: 7458d5b2-1bb7-7d87-7ce6-2b0c430b0155
• Version Independent ID: edf5bbd3-a3f0-5426-e985-31290f8afd05
• Content: YAML schema - Azure Pipelines
• Content Source: docs/pipelines/yaml-schema.md
• Product: devops
• Technology: devops-cicd
• GitHub Login: @vtbassmatt
• Microsoft Alias: macoope

[vtbassmatt]

@TingluoHuang or @ericsciple can you clarify here? schema.yml beginning around line 1410 says:

    - structure: mapping
      firstKey: checkout
      inherits: taskBase
      properties:
      - name: checkout
        type: string
        data:
          description: "Whether or not to check out the repository containing this pipeline definition"
          enum: "self,none"
      - name: clean
        type: string
        data:
          description: "Scorch the repo before fetching?"
          enum: "outputs,resources,all"

That said, workspace expects a suspiciously similar enum, so I'm wondering if this is a bug in the schema.

[vtbassmatt]

Ah, I found where the agent uses this value and it's indeed a boolean. So we have a bug in our parser schema.

[vtbassmatt]

Got to the bottom of it. It's a boolean, but it allows expressions, so we have to mark it as a string in the schema. And then we had a copy-paste error on what values are expected (which the parser doesn't use, but IntelliSense does). Both a doc fix and a product fix are inbound.