Accessible generates methods return types as IO[E, A] instead of ZIO[R, E, A]

[pierangeloc]

zio-macros version 0.4.0

@accessible generates capability accessors as IO[E, A] even if the service methods have ZIO[R, E, A].

E.g. in the test case zio.macros.access.ValidateAccessible the method

def get(id: Int): URIO[Example, String]                       = Example.>.get(id)

keeps compiling even with this signature

def get(id: Int): URIO[Any, String]                       = Example.>.get(id)

See tentative PR #27. Proposed solution fails with scala 2.12 and 2.11, but seems to work for 2.13

[pierangeloc]

Actually the #27 doesn't work on 2.13 either (on CI, but I was able to compile locally). Feel free to close it if it is not useful at all.