[Distributed] DeleteKey API for c10d TCP Store (#43963)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/43963
Added a DeleteKey API for the TCP Store
ghstack-source-id: 112939762
Test Plan:
Modified the existing get/set test to use delete. verified that the
correct keys were deleted and that the numKeys API returned the right values
Reviewed By: jiayisuse
Differential Revision: D23009117
fbshipit-source-id: 1a0d95b43d79e665a69b2befbaa059b2b50a1f66