…Writer/superTypeReader (#471)

Fixes #468

The basic problem is that with `enum A: case B`, Calling `implicit def
rw: RW[A] = macroR` will end up looking for a `R[B]`, which will trigger
`superTypeReader[B, A]`, which picks up the `rw` we are defining and
becoming an infinite recursion/loop.

The fix here is to ensure that when calling
`macroR[T]`/`macroW[T]`/`macroRW[T]`, that `superTypeReader` and
`superTypeWriter` do not trigger on type `[_, T]`. We can do that by
requiring that they take a `NotGiven[CurrentlyDeriving[T]]`, and
providing an implicit `CurrentlyDeriving[T]` in the
`macroR`/`macroW`/`macroRW` bodies.

Added some `compileError` tests to ensure these raise implicit not found
errors as expected

While `superTypeWriter`/`superTypeReader` had their signatures changed,
the fact that they are `inline` means there are no binary compatibility
concerns

This is only necessary for Scala 3, since Scala 2 doesn't have
`superTypeWriter`/`superTypeReader` in the first place due to diverging
implicit issues (see #459)