[Shipping Labels] Fix product icon color

[RafaelKayumov]

Closes: WOOMOB-81

Description

Applies template rendering mode for product and shipment icons to follow the color scheme.

Steps to reproduce

• Enable dark mode
• Log in to a test store with Woo Shipping plugin set up.
• Navigate to the Orders tab and select a completed order with several physical products.
• Tap on "Create shipping labels".
• Open the "Shipment details" bottom sheet.
• The "product" icon on "N items" row must contrast with the background and be readable.

Screenshots

Before	After

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[wpmobilebot]

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

	App Name	WooCommerce iOS Prototype
	Build Number	29592
	Version	PR #15564
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	4bbdd48
	Installation URL	72hpda1hbm690

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[itsmeichigo]

Thanks for the fix. I wonder if we should really replace the icon though, as it looks bolder than the original design:

I notice another icon below that's not supported in dark mode either. This would show up if you add a shipping line in the order creation step by tapping Add Shipping.

[dangermattic]

	1 Warning
⚠️	This PR is assigned to the milestone 22.3. This milestone is due in less than 2 days. Please make sure to get it merged by then or assign it to a milestone with a later deadline.

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[itsmeichigo]

Tested and confirmed that both icons look correctly in both light and dark modes.
I'll proceed to merge this PR.