Revert D29943356: .github: Migrate ecr_gc to github actions
Test Plan: revert-hammer
Differential Revision:
D29943356 (https://github.com/pytorch/pytorch/commit/8e0622abf125b5893a894c0cd9aacda309ac7199)
Original commit changeset: 493592baf2f7
fbshipit-source-id: f0e604aab2b828561adc3e8fabf0f39221e15615
