Defining internal-regex and import/external-module-folders together yields unexpected errors

In our monorepo we store our internal packages under `./packages`

So we tried a config like this:

```js
rules: {
'import/order': 'warn',
},
settings: {
'import/internal-regex': '^internal-', // This makes importing monorepo packages get treated as though they were 'relative-parent-imports'
'import/external-module-folders': ['node_modules', 'packages'],
}
```

But that makes a non-relative import throw this unexpected error

```js
import { foo } from 'internal-utils';
^--- // Relative imports from parent directories are not allowed.
```

Reproduce the configuration shown with the import/order rule, then trace how import/internal-regex and import/external-module-folders classify the internal-utils import together. Done means this non-relative import no longer receives the parent-directory error, with a regression check for the reported configuration.

Written by the indexing model from the issue text.