Generated html report does not mention license exceptions

**Describe the bug**
I have a variety of dependencies that are licensed under `GPL-3.0 WITH Classpath-exception-2.0`. The license check seems to work correctly but the generated html report puts the dependencies in the `GNU General Public License v3.0 only` section without any mentioning of the classpath exception. Mentioning the exception is quite important in this case and so I would like it to show up in the generated report.

**To Reproduce**
Steps to reproduce the behavior:
1. Create a new empty cargo project
2. Add a dependency to `fui_core = "0.12.0"` (which has `GPL-3.0 WITH Classpath-exception-2.0` license)
4. Run `cargo about init`
5. Modify the `about.toml` to this:
```
accepted = [
"Apache-2.0",
"MIT",
"GPL-3.0 WITH Classpath-exception-2.0",
"Unicode-DFS-2016",
]
```
7. Run `cargo about generate about.hbs > license.html`
8. Check the generated license.html

**Expected behavior**
Ideally the dependency would be listed in a `GNU General Public License v3.0 WITH Classpath-exception-2.0` section and the exception text would be appended to the "normal" license.

Start by reproducing the report with a new Cargo project, the fui_core dependency, about.toml, and the cargo about generate about.hbs > license.html command. Inspect the generated license.html and the handling of the GPL-3.0 WITH Classpath-exception-2.0 identifier; done means the dependency has its own exception-labelled section and the exception text is included.

Written by the indexing model from the issue text.