[torchelastic] Fix failing tests (#66440)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/66440
* Set correct name for test worker executable
* Remove `test_get_override_executable` from oss, there already test that tests the functionality
Test Plan: buck test mode/dev-nosan //caffe2/test/distributed/launcher/fb:launch_test
Reviewed By: d4l3k
Differential Revision: D31544853
fbshipit-source-id: e1e009b4b38830d3a78981f8f93c2314ed851695
