Bump intl from 0.19.0 to 0.20.0 in /background_isolate_channels (#2484)

Bumps [intl](https://github.com/dart-lang/i18n/tree/main/pkgs) from 0.19.0 to 0.20.0.
<details>
<summary>Release notes</summary>
<p><em>Sourced from <a href="https://github.com/dart-lang/i18n/releases">intl's releases</a>.</em></p>
<blockquote>
<h2>package:intl v0.20.0</h2>
<ul>
<li>Fix caching of messages in <code>CompositeMessageLookup</code>.</li>
<li>Type <code>numberFormatSymbols</code> as a <code>Map&lt;String, NumberSymbols&gt;</code>.</li>
<li>Type <code>dateTimeSymbolMap</code> as a <code>Map&lt;String, DateSymbols&gt;</code>.</li>
<li>Add example for pub.dev.</li>
<li>Fix issues with AM/PM markers.</li>
<li>Update to CLDR v44.1.</li>
<li>Require Dart <code>^3.3</code></li>
<li>Require <code>package:web</code> <code>^0.5.0</code>.</li>
<li>Support compiling to WASM.</li>
<li>Update to and account for <code>package:lints</code> <code>^4.0.0</code>.</li>
<li>rtl Detection fix in <code>bidi.dart</code> for Kordi Sorani &quot;ckb&quot;.</li>
<li>Update to CLDR v45.</li>
</ul>
<h2>package:intl_translation v0.20.0</h2>
<ul>
<li>Throw if the <code>Intl.select</code> <code>arg</code> is not in the list of <code>args</code>.</li>
<li>Support <code>package:intl</code> <code>0.19.0</code>.</li>
<li>Require Dart 3.0.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/dart-lang/i18n/commit/16647532c4a9e39bd683cba1599a9ef40c49ad6a"><code>1664753</code></a> Publish v0.20.1 of intl_translation (<a href="https://github.com/dart-lang/i18n/tree/main/pkgs/issues/913">#913</a>)</li>
<li><a href="https://github.com/dart-lang/i18n/commit/dddf276e6e7b7b81ea843fbbfea4edb951c48df1"><code>dddf276</code></a> add links to the individual issue trackers (<a href="https://github.com/dart-lang/i18n/tree/main/pkgs/issues/911">#911</a>)</li>
<li><a href="https://github.com/dart-lang/i18n/commit/9314522d920bc5cd9d00d05fbfedef21a30bd6a6"><code>9314522</code></a> Publish <code>v0.20.0</code> of <code>package:intl</code> (<a href="https://github.com/dart-lang/i18n/tree/main/pkgs/issues/909">#909</a>)</li>
<li><a href="https://github.com/dart-lang/i18n/commit/b437a86a59c30190948236d7e98c754b9fa262ad"><code>b437a86</code></a> No public description</li>
<li><a href="https://github.com/dart-lang/i18n/commit/3820422b0ce8f9daa9b6ae913d18a309a95ffafc"><code>3820422</code></a> Adapt <code>package:messages</code> to be loading mechanism independent (<a href="https://github.com/dart-lang/i18n/tree/main/pkgs/issues/843">#843</a>)</li>
<li><a href="https://github.com/dart-lang/i18n/commit/d6d514b812dc769ed855aece2eb7159bab5dbbb9"><code>d6d514b</code></a> Update CHANGELOG.</li>
<li><a href="https://github.com/dart-lang/i18n/commit/f9f3ade2dcc3a2753bd78d080f51afa0eb6e96d4"><code>f9f3ade</code></a> Pass a language version to DartFormatter().</li>
<li><a href="https://github.com/dart-lang/i18n/commit/7a66431c0afd26b60777c3152b92800bef8550d5"><code>7a66431</code></a> No public description</li>
<li><a href="https://github.com/dart-lang/i18n/commit/8ec20fc78a1f35b6a33b5108d20964d13a401cde"><code>8ec20fc</code></a> Update currency symbol for <code>MKD</code> (<a href="https://github.com/dart-lang/i18n/tree/main/pkgs/issues/891">#891</a>)</li>
<li><a href="https://github.com/dart-lang/i18n/commit/4e48884a1dee945d8a408a34d2d8d9c36065ae92"><code>4e48884</code></a> No public description</li>
<li>Additional commits viewable in <a href="https://github.com/dart-lang/i18n/commits/intl-v0.20.0/pkgs">compare view</a></li>
</ul>
</details>
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</details>

background_isolate_channels/pubspec.yaml

@@ -12,7 +12,7 @@ dependencies:
   cupertino_icons: ^1.0.2
   flutter:
     sdk: flutter
-  intl: ^0.19.0
+  intl: ^0.20.0
   path: ^1.8.2
   path_provider: ^2.0.11
   shared_preferences: ^2.0.15