Update matcher dependency and prepare to publish (#1566)

Copy the changelog from `matcher` into `test` since this is where most
users will see it.

Specify the generic type for a `fold` call.
The changed argument type for `expect` from `dynamic` to `Object?`
changes the inferred generic for the cal to `fold` as well, which causes
the function argument to no longer fit the expected static type since it
doesn't have `dynamic` to mask the implicit casts.
7 files changed