Unable to disable the Project Serve Integration after restoring all collections including configuration database to test environmnet

Hi,

We have restored the Production server backups including configuration database to a test environment. Among these collections some collection databases are integrated with Project Server and we unable to un-register the Test TFS server with Production Project Server, due to which the Project Server Sync job (Test Server) is running for every 30 seconds and failing and is flooding the Event Viewer with 9000 errors. 

Let us know how to disable the TFS-Project Server integration.

Thanks