Update Tap to Pay contactless limit description for the UK

[staskus]

Closes: #14723

Description

Based on the clarification made in pdfdoF-5ZW-p2#comment-7215, I'm adding a bit more detail into the UK TTP payment limit description.

Steps to reproduce

1. Log into the UK store pdfdoF-5Vk-p2 on iPhone
2. Go to Menu -> Payments -> About Tap to Pay
3. Confirm the first page shows a contactless limit notice at the bottom

Testing information

No extra tests required for localization change.

Screenshots

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• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

Reviewer (or Author, in the case of optional code reviews):

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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 all devices (phone/tablet) and no regressions are added.

[wpmobilebot]

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

	App Name	WooCommerce iOS
	Build Number	pr14758-4e4fd08
	Version	21.3
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	4e4fd08
	App Center Build	WooCommerce - Prototype Builds #12286

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[iamgabrielma]

Works as described!

We just happen to have a test for that string! test_for_gb_configuration_a_formatted_limit_paragraph_is_provided() which doesn't pass CI now, I'll approve the PR just be sure to address it before merge :D