Copilot Skills for tox

The ML team has already created skills for mypy/pylint, these skills should be generalized for all libraries. We should also add the other main tox commands, basically all of this https://github.com/Azure/azure-sdk-for-python/blob/main/doc/dev/tests.md#running-checks-locally. Also creating a skill for test creation would be good.

So:
- [x] Skill for Black
- [x] Skill for mypy
- [x] Skill for pylint
- [ ] Skill for tests building
- [ ] A skill for 1 creating samples and then making them part of the readme (Though this issue would need to be fixed first. https://github.com/Azure/azure-sdk-for-python/issues/44805)