[CI] Enure the pwsh is in the right dir. (dotnet#13370)

Follow up of dotnet#13264

We need to be sure that the pwsh is executed from the right dir, the
simplest way is to set the working dir for the step.

eng/pipelines/common/pack.yml

@@ -48,18 +48,24 @@ steps:
  - pwsh: ./build.ps1 --target=dotnet --configuration="Release" --verbosity=diagnostic --nugetsource="${{ parameters.nugetFolder }}"
  displayName: 'Install .NET'
  retryCountOnTaskFailure: 3
+ workingDirectory: ${{ parameters.checkoutDirectory }}
  env:
  DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token)
  PRIVATE_BUILD: $(PrivateBuild)
+
  - pwsh: ./build.ps1 --target=dotnet-pack --configuration="Release" --verbosity=diagnostic --nugetsource="${{ parameters.nugetFolder }}"
  displayName: 'Pack .NET Maui'
  name: PackMaui
+ workingDirectory: ${{ parameters.checkoutDirectory }}
  env:
  DOTNET_TOKEN: $(dotnetbuilds-internal-container-read-token)
  PRIVATE_BUILD: $(PrivateBuild)
+
  - ${{ if eq(parameters.platform, 'Windows') }}:
  - pwsh: ./build.ps1 --target=dotnet-diff --configuration="Release" --verbosity=diagnostic
  displayName: 'Diff .NET Maui artifacts with NuGet'
+ workingDirectory: ${{ parameters.checkoutDirectory }}
+
  # artifacts
  - task: CopyFiles@2
  condition: always()