commit for PR microsoft#15217

Added to avoid conflicts in integration

Author: vineethkuttan

.ado/templates/prep-and-pack-nuget.yml

@@ -73,6 +73,9 @@ steps:
           artifact: ${{ parameters.artifactName2 }}.${{ slice.platform }}.${{ slice.configuration }}
           path: ${{parameters.nugetroot}}/${{ parameters.artifactName2 }}/${{ slice.platform }}/${{ slice.configuration }}
 
+  - pwsh: yarn build
+    displayName: Run yarn build
+
   - task: PowerShell@2
     displayName: Copy MSRN Resources to NuGet layout
     inputs:

vnext/.gitignore

@@ -74,6 +74,7 @@ Generated Files/
 /WindowsSampleCSharpApp/obj/
 /target/
 /x64/
+/codegen/
 Examples/WindowsSampleApp/Generated Files/
 Examples/WindowsSampleApp/build
 Examples/TypeScript/Generated Files/