Error on zero tab width (#6429)
## Summary
Error if `tab-size` is set to zero (it is used as a divisor). Closes
#6423.
Also fixes a typo.
## Test Plan
Running ruff with a config
```toml
[tool.ruff]
tab-size = 0
```
returns an error message to the user saying that `tab-size` must be
greater than zero.
