Fix pencil icon color to work both on light and dark mode

[hafizrahman]

Description

When beta testing 21.4, @itsmeichigo reported this issue where the pencil icon for editing status in Order Details is hard to see:

This PR sets the icon to use color_primary, which is commonly used in other tappable icons in the app. The result is like this:

Additional discussion

The affected icon is actually used in different places in the app:

However, we're not hearing about color issue in dark mode in other places where this icon is used. This is because whenever it is used, either in Compose or XML, its tint is also set separately there (e.g: with app:iconTint="@color/color_primary" or tint = MaterialTheme.colors.primary).

With the change introduced in this PR, technically, those separate color settings are not needed anymore and can be deleted. However, deleting them means it will require us extra time to check each individual area that uses it. This will have to be done not just during PR review, but also later during beta testing.

Thinking about that trade-off, I decided not to remove the individual setting and just leave them be, to save us time.

Steps to reproduce

Build app, then edit an Order in Dark Mode. Ensure the pencil icon next to the Order status is visible in purple color, similar to screenshot above.

Testing information

The tests that have been performed

Listed above.

Images/gif

Added above.

• 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.

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 big (tablet) and small (phone) in case of UI changes, and no regressions are added.

[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	20e422d
	Direct Download	woocommerce-wear-prototype-build-pr13316-20e422d.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	20e422d
	Direct Download	woocommerce-prototype-build-pr13316-20e422d.apk

[irfano]

LGTM! 👍🏻