Update condition so that signing exe doesn't fail for netcore
Update condition so that signing exe doesn't fail for netcore

SonarSource-VisualStudio/sonar-msbuild-runner,duncanpMS/sonar-msbuild-runner,duncanpMS/sonar-msbuild-runner,SonarSource-VisualStudio/sonar-scanner-msbuild,duncanpMS/sonar-msbuild-runner,SonarSource-VisualStudio/sonar-scanner-msbuild,SonarSource/sonar-msbuild-runner,SonarSource-VisualStudio/sonar-scanner-msbuild,SonarSource-DotNet/sonar-msbuild-runner,SonarSource-VisualStudio/sonar-msbuild-runner