[Tracks] Use invariant locale when converting stat names from the enum types

[hichamboushaba]

Closes: #12986

Description

This PR fixes an issue where some Tracks events are ignored when using Turkish language, when an event uses an i character, the cause is that we were using the device Locale when lowercasing from the enum name, but we should be using the invariant locale here.

Steps to reproduce

1. Switch your phone's language to Turkish.
2. Open the app.

Testing information

Check logcat and confirm that no EventNameException is thrown.

The tests that have been performed

^

• I have considered if this change warrants release notes and have added them to RELEASE-NOTES.txt if necessary. Use the "[Internal]" label for non-user-facing changes.

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• The PR is small and has a clear, single focus, or a valid explanation is provided in the description. If needed, please request to split it into smaller PRs.
• Ensure Adequate Unit Test Coverage: The changes are reasonably covered by unit tests or an explanation is provided in the PR description.
• Manual Testing: The author listed all the tests they ran, including smoke tests when needed (e.g., for refactorings). The reviewer confirmed that the PR works as expected on big (tablet) and small (phone) in case of UI changes, and no regressions are added.

[dangermattic]

	1 Warning
⚠️	This PR is assigned to the milestone 21.2 ❄️. The due date for this milestone has already passed. Please assign it to a milestone with a later deadline or check whether the release for this milestone has already been finished.

	1 Message
📖	This PR contains changes to Tracks-related logic. Please ensure (author and reviewer) the following are completed: The tracks events must be validated in the Tracks system. Verify the internal Tracks spreadsheet has also been updated. Please consider registering any new events. The PR must be assigned the category: tracks label.

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[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce-Wear Android by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce-Wear Android
	Platform	⌚️ Wear OS
	Flavor	Jalapeno
	Build Type	Debug
	Commit	5ba58b2
	Direct Download	woocommerce-wear-prototype-build-pr12987-5ba58b2.apk

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce Android by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce Android
	Platform	📱 Mobile
	Flavor	Jalapeno
	Build Type	Debug
	Commit	5ba58b2
	Direct Download	woocommerce-prototype-build-pr12987-5ba58b2.apk

[JorgeMucientes]

Change makes sense and works as expected. Great job at catching this issue @hichamboushaba.

Out of curiosity. I wonder if instead of relying on Locale.ROOT we could rely better on Locale.ENGLISH since all tracking event names are in English

[hichamboushaba]

Out of curiosity. I wonder if instead of relying on Locale.ROOT we could rely better on Locale.ENGLISH since all tracking event names are in English

I don't have a strong opinion about this, but personally I feel that Locale.ROOT is the better choice for handling locale operations targetted as a computer, vs real locales that should be used when the output is targetted at users.
For this case, our output is targetted at computer, so it made more sense (even though I'm not using it explicitly, Kotlin's extension will use it behind the scenes), C# also has a similar concept with its InvariantCulture, and it's recommended to use it when we need a stable output, even though the same article says that it's associated with the English language.