Fix config reference

Author: deathly809

src/StackAdmin/Azs.InfrastructureInsights.Admin/Tests/packages.config

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="Microsoft.AzureStack.Management.InfrastructureInsights.Admin" version="0.2.0" targetFramework="net452" />
+  <package id="Microsoft.AzureStack.Management.InfrastructureInsights.Admin" version="0.2.0-preview" targetFramework="net452" />
 </packages>