Depricate Lockable for 1.11+

[This PR](https://github.com/JuliaLang/julia/pull/52898) introduced a type `Lockable` into base. With that change, this functionality should be removed from version of ConcurrentUtilities for julia 1.11+. This would be a breaking change if I am not mistaken, but would be required to avoid confusion about two different versions of `Lockable` with overlapping function.