Bump dartdoc in to ~0.32.4
Bump dartdoc in to ~0.32.4

Change-Id: I526c928b54bfacb7abd863507820747581870f46
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/159401
Reviewed-by: Keerti Parthasarathy <50d1d8bfaf73a210aebf5aef847d5b7b93955336@google.com>
Commit-Queue: Samuel Rawlins <5cf2cac5eec2ad6d0eb2b0f4ff6af9a590ce2bf6@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk