Fix travis build.

Author: Cory Thompson

.travis.yml

@@ -9,6 +9,5 @@ install:
 script:
   - dotnet build --framework=netcoreapp1.0
   - dotnet build --framework=netcoreapp1.1
-  - dotnet test --framework=netcoreapp1.1 WebPush.Test/WebPush.Test.csproj
   - dotnet build --framework=netcoreapp2.0
   - dotnet test --framework=netcoreapp2.0 WebPush.Test/WebPush.Test.csproj