Remove usage of thread-unsafe random number serivce from CscDigitToCscRDOTool
This commit removes the usage of IAtRndmGenSvc from CscDigitToCscRDOTool
and replaces it with the thread-safe IAthRNGSvc.
These changes are a necessary step towards reproducible digitization output between single-threaded and multi-threaded jobs. The digitization and overlay output will change due to this commit as the random number seeding will be slightly different.