Fix SonarQube Cloud finding(s) in GitHub Actions workflow template for .NET

Recently, SonarQube Cloud rightly complained about the way secrets are passed to the run command when copying and pasting the GitHub Actions workflow for .NET from SonarQube Cloud Analyze a project with a GitHub Action wizard.

The recommended way for passing secrets to a run command is as follows:

      - name: Build and analyze
        env:
          SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
        shell: powershell
        run: |
          ${{ runner.temp }}\scanner\dotnet-sonarscanner begin /k:"SONAR_PROJECT_KEY" /o:"SONAR_ORG_ID" /d:sonar.token="$env:SONAR_TOKEN"
          dotnet build
          ${{ runner.temp }}\scanner\dotnet-sonarscanner end /d:sonar.token="$env:SONAR_TOKEN"

Instead of "${{ secrets.SONAR_TOKEN }}" use "$env:SONAR_TOKEN"

Can you please fix / improve this?