Use simple typeable for simple case classes

[dwickern]

I ran into this migrating some code from Scala 2 to 3.

Missing Typeable for field of case class shapeless3.typeable.TypeableTests.CaseClassWithEnumeration [614:48]

[joroKr21]

It's probably missing typeable for enumeration

[dwickern]

Actually the problem is we don't need a namedCaseClassTypeable for these simple case classes, we can use a namedSimpleTypeable like Shapeless 2 does. This also avoids an unnecessarily large generated Typeable implementation.

[joroKr21]

That makes sense 👍