Update release.yml for Azure Pipelines (#2051)

Author: vicancy

.azure/pipelines/release.yml

@@ -144,12 +144,6 @@ extends:
                   inputs:
                     command: custom
                     arguments: init artifacts $(LocalFeed)
-                - task: MSBuild@1
-                  displayName: Test Restoring Packages
-                  inputs:
-                    solution: build/package-test.3.proj
-                    msbuildArchitecture: x64
-                    msbuildArguments: /p:$(MSBuildProperties) /p:UseLocalFeed=true /p:LocalFeed=$(LocalFeed) /t:Restore
               - ${{ if or( eq(parameters.isFinalBuild, false),  eq(parameters.releaseEmulator, true)) }}:
                 - task: DotNetCoreCLI@2
                   displayName: dotnet pack emulator when only dev or release emulator