cg-detection pipeline is failing due to incorrect pool usage

[lbussell]

Failing pipeline run: https://dev.azure.com/dnceng/internal/_build/results?buildId=2534703&view=results

  ##[error]The pipeline is not valid. Could not find a pool with name $(default1ESInternalPoolName). The pool does not exist or has not been authorized for use. For authorization details, refer to https://aka.ms/yamlauthz.

/cc @ellahathaway, perhaps something was missing from #1167?

[ellahathaway]

It looks like this pipeline isn't importing the common variables template where default1ESInternalPoolName is specified. I think that this pipeline should import the template and use the 1es official template too