dpg sdkautomation, fix variable

[XiaofeiCao]

Description

Fix https://dev.azure.com/azure-sdk/internal/_build/results?buildId=3940596&view=logs&j=a8a7a537-82b0-583c-7971-bac70b9822ca&t=37e3947b-3cfb-5d36-86ba-0e22bb7dbc33
This was added in test-repo-billy/azure-sdk-for-java. Forgot to sync to feature branch..

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[XiaofeiCao]

/check-enforcer override