set stopOnFail to true for dotnet-core.yml

.github/workflows/dotnet-core.yml

@@ -32,6 +32,7 @@ jobs:
 
     - name: Test
       run: |
+        sed -i 's/"stopOnFail": false/"stopOnFail": true/g' UnitTests/xunit.runner.json
         dotnet test --no-restore --verbosity normal --collect:"XPlat Code Coverage"  --settings UnitTests/coverlet.runsettings
         mv -v UnitTests/TestResults/*/*.* UnitTests/TestResults/