Remove documentation about WebSocketChannel.new in doc comment

[benjaminpjones]

The constructor was removed in 3.0.0 according to the changelog, but the doc comment was not updated.

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• I’ve reviewed the contributor guide and applied the relevant portions to this PR.

[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:cronet_http	1.5.0	already published at pub.dev
package:cupertino_http	2.4.0-wip	WIP (no publish necessary)
package:http	1.6.0-wip	WIP (no publish necessary)
package:http2	3.0.0	ready to publish	http2-v3.0.0
package:http_multi_server	3.2.2	already published at pub.dev
package:http_parser	4.1.2	already published at pub.dev
package:http_profile	0.1.1-wip	WIP (no publish necessary)
package:ok_http	0.1.1-wip	WIP (no publish necessary)
package:web_socket	1.0.1	already published at pub.dev
package:web_socket_channel	3.0.4	ready to publish	web_socket_channel-v3.0.4

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[github-actions]

PR Health

Breaking changes ✔️

Package	Change	Current Version	New Version	Needed Version	Looking good?
web_socket_channel	None	3.0.3	3.0.4-wip	3.0.3	✔️

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Changelog Entry ✔️

Package	Changed Files

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Coverage ✔️

File	Coverage
pkgs/web_socket_channel/lib/src/channel.dart	💚 50 %

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API leaks ✔️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

Package	Leaked API symbol	Leaking sources

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License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

Files
no missing headers

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Files
pkgs/http/example/main.dart

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[brianquinlan]

Thanks so much for your contribution!

[brianquinlan]

Thanks so much for your contribution!