Wrong return values for setters when generating .d.ts typings

Aloha!

When I generate .d.ts typings with any grpc-web version > 1.0.7 all setter-functions now return their class rather than void.

E.g. what I expect: setToken(value: Uint8Array | string): void;

What is generated: setToken(value: Uint8Array | string): SaltEntry

I guess this is because of a bug introduced with commit #747 (line 924, 927).