Update Turkish Lira (TRY) symbol to ₺ (U+20BA)

[fevzican]

This PR updates the Turkish Lira (TRY) currency symbol in the simpleCurrencySymbols map from "TL" to "₺" (Unicode: U+20BA). This change aligns with the official symbol for Turkish Lira introduced in 2012.

No functional changes are introduced, as this update only modifies the symbol representation. The change ensures consistency and accuracy in displaying the currency.

Why
The current symbol "TL" is outdated. The Unicode character "₺" is the official and globally recognized symbol for Turkish Lira.

Relevant Issues
N/A – This is a minor update to align with modern standards.

Checklist
I’ve reviewed the contributor guide and applied the relevant portions to this PR.
I’ve verified that the change works as expected and doesn’t introduce any regressions.
No additional tests were added since this is a minor symbol update for Turkish Lira (TRY). If a dedicated test is required, I am happy to add one

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:intl	0.20.2	ready to publish	intl-v0.20.2
package:intl4x	0.10.1	already published at pub.dev
package:intl_translation	0.20.1	already published at pub.dev
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	0.20.2	0.20.2	0.20.2	✔️

Changelog Entry ✔️

Package	Changed Files

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

Coverage ✔️

File	Coverage
pkgs/intl/lib/src/intl/constants.dart	💚 100 %

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

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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

All source files should start with a license header.

[mosuem]

Thanks for the PR! Please write a note in the changelog, then this is ready to be merged.

[fevzican]

Thank you for your feedback! I've added a note in the changelog. Please let me know if there's anything else you'd like me to adjust. @mosuem