Publish v0.20.0 of package:intl

[mosuem]

Fixes #908
Fixes #793

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:intl	0.20.0	ready to publish	intl-v0.20.0
package:intl4x	0.10.1	already published at pub.dev
package:intl_translation	0.20.1-wip	WIP (no publish necessary)
package:messages_shrinker	0.2.2-wip	WIP (no publish necessary)

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?
intl	None	0.20.0-wip	0.20.0	0.20.0	✔️

Changelog Entry ✔️

Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

Coverage ✔️

File	Coverage

This check for test coverage is informational (issues shown here will not fail the PR).

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 symbols
intl	StringStack DateBuilder

This check can be disabled by tagging the PR with skip-leaking-check.

License Headers ✔️

// Copyright (c) 2024, 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

All source files should start with a license header.

Unrelated files missing license headers

Files
pkgs/messages/examples_flutter/my_application/lib/src/empty_de.dart
pkgs/messages/examples_flutter/my_application/lib/src/empty_en.dart

[devoncarew]

lgtm

Do we also want to widen the dep range on intl from https://github.com/dart-lang/i18n/blob/main/pkgs/intl_translation/pubspec.yaml#L20, and publish that package?

We should also pre-create a 'version solving failed for 0.20.0 ...' issue, pin it, and un-pin the old one.