Refactor remaining distributed tests (#2216)
* batch of refactored tests
* more test refactoring
* fp16 test refactor
* more refactors
* added DistributedFixture class
* applied DistributedFixture to first batch of tests as a trial
* added DistributedFixture test and documentation
* last tests
* fixes for refactored tests
* remove subdirs in workflow files
* fix pytest syntax error
* fix another syntax error
* update imports
* use DistFixture with elastic checkpoint test
* missing import
* update to shared class tmpdir for elastic test
* moved test files
* avoid duplicate test file name
* last refactor and moving test files
* formatting
* fix broken import
* testing forked AMD tests
* update abstract method
* use blob storage for accelerate and transformers tests
* upgrade torch for acclerate CI
Co-authored-by: Olatunji Ruwase <olruwase@microsoft.com>
