Don't show choco install progress

RehanSaeed · RehanSaeed · commit 7f91f038a41e · 2018-06-06T13:08:08.000+01:00
diff --git a/appveyor.yml b/appveyor.yml
@@ -22,7 +22,7 @@ environment:
 
 build_script:
 # Install .NET Core SDK
-- ps: choco install dotnetcore-sdk -y --version 2.1.300
+- ps: choco install dotnetcore-sdk --no-progress --confirm --version 2.1.300
 - ps: .\build.ps1
 
 test: off
