CI server does not have valid dev-cert

appveyor.yml

@@ -54,7 +54,6 @@ before_build:
 
       [Environment]::SetEnvironmentVariable("PATH", $env:Path, "User")
 
-
       Write-Output "Restoring dotnet projects ..."
 
       dotnet restore amqp-dotnet.sln

test/Common/Extensions.cs

@@ -81,7 +81,7 @@ namespace Test.Common
             X509Certificate2Collection collection = store.Certificates.Find(
                 X509FindType.FindBySubjectName,
                 certFindValue,
-                true);
+                false);
             if (collection.Count == 0)
             {
                 cert = null;