Use the same logic as dbt-core or the paths for the project and profiles

**Describe the solution you'd like**
If I have a dbt `profiles.yml` in my current working directory, I'd like to be able to do this:

```shell
data-diff --dbt
```

**Describe alternatives you've considered**
This is the way to do it currently:
```shell
data-diff --dbt --dbt-profiles-dir .
```

**Additional context**
I'll open a PR for this.