Skip checkout for Publish CI pipelines

.ci/publish-nightly.yml

@@ -13,7 +13,7 @@ jobs:
     pool:
       vmImage: ubuntu-latest
     steps:
-
+    - checkout: none
     - task: DownloadPipelineArtifact@2
       displayName: Download the Windows Setup Artifact
       inputs:

.ci/publish-release.yml

@@ -15,7 +15,7 @@ jobs:
     pool:
       vmImage: ubuntu-latest
     steps:
-
+    - checkout: none
     - task: DownloadPipelineArtifact@2
       displayName: Download the Windows Setup Artifact
       inputs: