`doc` with `--test` fails on top level `@main`

[Gedochao]

Version(s)
1.7.1

To Reproduce
Try to generate docs with the doc command for the following test input source

// example.test.scala
@main def main() = println("Hello World!")

scala-cli doc . --test

Fails with:

class example.test$package cannot be unpickled because no class file was found for denot: val <none>
1 warning found
1 error found
[error]  Scaladoc generation failed (exit code: 1)

Expected behaviour
Should work, same as in main scope.

[Gedochao]

What's interesting, this works when @main is wrapped in an object.
I wonder if the issue isn't in scaladoc itself. 🤔
The following works:

object whatever {
  @main def main() = println("Hello World!")
}

[Gedochao]

Minimised and raised upstream:

• The doctool has trouble with files named .test.scala containing top-level @main function scala/scala3#22866