Merge pull request #1262 from microsoftgraph/andrueastman/fixCheckout

Fix checkout branches

Author: andrueastman

.azure-pipelines/generation-pipeline.yml

@@ -17,12 +17,12 @@ resources:
      type: github
      endpoint: microsoftgraph (22)
      name: microsoftgraph/msgraph-sdk-dotnet
-     ref: master
+     ref: main
    - repository: msgraph-beta-sdk-dotnet
      type: github
      endpoint: microsoftgraph (22)
      name: microsoftgraph/msgraph-beta-sdk-dotnet
-     ref: master
+     ref: main
    - repository: msgraph-sdk-php
      type: github
      endpoint: microsoftgraph (22)