Workaround to compile on circle

.circleci/config.yml

@@ -6,13 +6,19 @@ jobs:
     steps: 
       - checkout
   test:
-    docker:
-      - image: microsoft/dotnet:2.1.403-sdk-alpine3.7
+    machine: true
     steps:
       - checkout
       - run:
           command: |
+            lsb_release -a
+            wget -q https://packages.microsoft.com/config/ubuntu/14.04/packages-microsoft-prod.deb
+            sudo dpkg -i packages-microsoft-prod.deb
+            sudo apt-get install apt-transport-https
+            sudo apt-get update
+            sudo apt-get install dotnet-sdk-2.1
             dotnet --info
+            rm global.json
             dotnet build /p:TreatWarningsAsErrors=true
             cd BTCPayServer.Tests
             dotnet test --filter Fast=Fast