Sorter violates directives_ordering lint rule when file has named imports

**Describe the bug**

In a file that contains relative import paths, and an absolute path to a named import, then the Dart linting rule `directives_ordering` fails.

**To Reproduce**

1. In your `analysis_options.yaml` file, enable the `directives_ordering` option (more info here: http://dart-lang.github.io/linter/lints/directives_ordering.html)
2. Create a file that contains the following:
1. An absolute path to a project import
2. An absolute path to a named project import
3. A relative path to a project import
3. Run the sorter
4. You should see a linting error (I'm using VSCode)

**Expected behavior**

The import sorter should respect conventional dart styling guidelines.

**Screenshots**
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**Meta Information:**
- Dart Version: SDK version `>=2.7.1 <3.0.0`
- `import_sorter` Version: 4.2.1
- Is it a Flutter project? No
- What version of Flutter are you using (if flutter project): N/a

**Additional context**
Add any other context about the problem here.