Upgrade project(s) to the SDK-style project format

There are 2 project(s) using the non-SDK-style project format.
This is an auto-generated issue, detailed and discussed in [dotnet/docs#22271](https://github.com/dotnet/docs/issues/22271).

- [ ] non-lts/project.json
- [ ] non-lts/ReallyOld.xproj

Consider upgrading the project(s) to the [SDK-style format](https://docs.microsoft.com/dotnet/standard/frameworks).

If any of these projects listed in this issue are intentionally demonstrating the old project style,
you can optionally configure to ignore these results in future automation executions.
Create a (or update the) *dotnet-versionsweeper.json* file at the root of the repository and
add an `ignore` entry following the
[globbing patterns detailed here](https://learn.microsoft.com/dotnet/core/extensions/file-globbing).

```json
{
"ignore": [
"**/path/to/example.csproj"
]
}
```