chore(workerbee): Updated stream_channel version contraints

[tyllark]

Description of changes:
Currently MessagePortChannel uses StreamChannelMixin as a Mixin, as of Dart SDK 3.0 classes need to declare if they support Mixins, which StreamChannelMixin does and is further confirmed in this issue.

Since stream_channel 2.1.3 Updates the Dart SDK to 3.3 (from 2.19) I've added a version constraint to prevent build runner from failing.

[SEVERE] build_web_compilers:entrypoint on lib/src/worker/workers.release.dart:
ExitCode:1
StdOut:
org-dartlang-app:///packages/worker_bee/src/js/message_port_channel.dart@614+1:
Error: The class 'StreamChannelMixin' can't be used as a mixin because it isn't a mixin class nor a mixin.
Error: Compilation failed.

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