Update the build check workflow

### Current Behavior

We install the wheel, check that the package is installed, then immediately install the sdist, and check that the package is installed again.

### Expected Behavior

We should be validating the packages in isolated environments. This arose from the `setuptools` / `packaging` issue for `dbt-core<1.4`, but it's something we should do for current versions as well. See https://github.com/dbt-labs/dbt-core/issues/10465 for the analogous `dbt-core` issue.