twists beta regression

[est31]

twists commit https://github.com/rustyhorde/twists/commit/4490db4201265c28c9f05f469d0d010181f65b22 regressed from stable to beta (full log):

Aug 17 12:50:15.558 INFO kablam! error: type `slog::NeverStruct` is private
Aug 17 12:50:15.558 INFO kablam!   --> /cargo-home/registry/src/github.com-1ecc6299db9ec823/twist-jwt-0.3.1/src/client.rs:16:5
Aug 17 12:50:15.559 INFO kablam!    |
Aug 17 12:50:15.559 INFO kablam! 16 |     stdout: Option<Logger>,
Aug 17 12:50:15.559 INFO kablam!    |     ^^^^^^^^^^^^^^^^^^^^^^
Aug 17 12:50:15.559 INFO kablam! 

cc @rustyhorde

[est31]

Similarly for twisty (log).

[alexcrichton]

I believe the compiler/lang teams won't be reverting #42125, so I'm going to close this regression tracker.