Fix Accelerate CLI CPU option + small fix for W&B tests

[muellerzr]

Fix Accelerate CLI CPU option + Small W&B testfix

What does this add?

• Change CPU param to use convert_yes_no_to_bool in the CLI Config
• Changes the logic for W&B .log tests to be assertTrue and "str" in output

Why is this needed?

• Fixes an undocumented issue where the Accelerate Config CPU param expected a boolean argument, but it was phrased in a way where it seemed like yes/no could be passed in forums post
• Noticed that the CI seemed to be slightly unstable with the W&B log parsing (unsurprising), so rather than a self.assertEqual I opted for a self.assertTrue and runs an in check, since we only care that the value itself is in the log, with potentially a little bit of noise

[sgugger]

Thanks a lot for fixing!

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.