Allow passing AzDO build into job/execute-sdl.yml

[dagood]

In #7611, I added a way to pass AzDOBuildId etc. into eng/common/templates/job/execute-sdl.yml so the template works for non-BAR scenarios like mine (microsoft/go). It looks like this broke in some refactor PRs, and now the Maestro/BAR-based setup-maestro-vars.yml runs unconditionally.

The template still has these:

    - name: AzDOBuildId
      value: ${{ parameters.AzDOBuildId }}

So, all I had to do in this PR was make setup-maestro-vars.yml conditional. 🙂

The change works in my build. I'm not sure if any more testing is necessary: nobody else sets these template parameters (I did some searching in dotnet), and the change is pretty simple.

@adiaaida, @garath, can you take a look, or loop in more people involved in Guardian/SDL currently?

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To double check:

• The right tests are in and and the right validation has happened. Guidance: https://github.com/dotnet/arcade/tree/main/Documentation/Validation