[Woo POS] [Variable Products] Update info banner to include variable products

[joshheald]

Closes: #14925

Description

This PR updates the "Simple Products Only" banner and modal to show that we also support variable products, and non-downloadable virtual products.

Steps to reproduce

Reinstall the app if you don't currently see the info banner at the top of the item list
Launch the app and go to POS
Observe that the banner and the modal it opens mention virtual products, not simple products only.

Change the feature flag variableProductsInPointOfSale to true

Repeat the above test but observe that the banner and modal have the previous text.

Testing information

Screenshots

Feature flag disabled

before.mp4

Feature flag enabled

after.mp4

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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):

Please make sure these conditions are met before approving the PR, or request changes if the PR needs improvement:

• 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	pr14926-6f4c134
	Version	21.4
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	6f4c134
	App Center Build	WooCommerce - Prototype Builds #12606

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[iamgabrielma]

Looks good! 🚢