[EZ] [BE] Remove (now) unused scale config (pytorch#138511)

Final step of moving scale config files to test-infra repo.  Details in pytorch/test-infra#5767

Scale configs are now read from test-infra.  This PR is just cleaning up stale files
Pull Request resolved: pytorch#138511
Approved by: https://github.com/clee2000

Author: ZainRizvi