unit test

[AmberLJC]

Why are these changes needed?

Auto pytest and some unit tests.

Related issue number

Checks

• [ ] I've included any doc changes needed for https://fedscale.readthedocs.io/en/latest/
• [ ] I've made sure the following tests are passing.
• Testing Configurations
  • [ ] Dry Run (20 training rounds & 1 evaluation round)
  • [ ] Cifar 10 (20 training rounds & 1 evaluation round)
  • [ ] Femnist (20 training rounds & 1 evaluation round)