Properly type unsubscribe Subjects

[jamesrwelch]

A lot of components declare an unsubscribe$ Subject and specify it without a dynamic type:

private unsubscribe$ = new Subject();

These should be defined using a dynamic type to help the type checker:

private unsubscribe$ = new Subject<void>();

This is not an issue at the moment, but after an upgrade to angular 14, and the latest typescript libraries, it will cause issues.