Cleanup of unused list in adam.py (#53874)
Summary:
Code cleanup.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/53874
Reviewed By: jbschlosser
Differential Revision: D27036819
Pulled By: ngimel
fbshipit-source-id: c267e20c8d91224cd3c01b302a75f43aa309b560
