Improve progress bar for adversaries

[mzweilin]

What does this PR do?

This PR tries to improve the progress bar for adversaries.

• [x] Replace title Epoch n with Attack.
• [x] Fix negative rate.
• [x] Make a default progress bar for adversary.
• [x] Turn on/off progress bar in attack configuration.
• [x] Hide progress bar for FGSM by default.
• [x] Display multiple progress bars in the multi-rank environment.
• [x] Display gain instead of loss.

Type of change

Please check all relevant options.

• [x] Improvement (non-breaking)
• [ ] Bug fix (non-breaking)
• [ ] New feature (non-breaking)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] This change requires a documentation update

Testing

Please describe the tests that you ran to verify your changes. Consider listing any relevant details of your test configuration.

• [x] pytest
• [x] python -m mart experiment=CIFAR10_CNN_Adv trainer=gpu achieves 70.09% accuracy.
• [x] python -m mart experiment=CIFAR10_CNN_Adv trainer=ddp trainer.devices=2 model.optimizer.lr=0.2 trainer.max_steps=2925 datamodule.ims_per_batch=256 achieves 69.84% accuracy.

Before submitting

• [x] The title is self-explanatory and the description concisely explains the PR
• [x] My PR does only one thing, instead of bundling different changes together
• [ ] I list all the breaking changes introduced by this pull request
• [x] I have commented my code
• [ ] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes
• [x] I have run pre-commit hooks with pre-commit run -a command without errors

Did you have fun?

Make sure you had fun coding 🙃