Remove zeroDataStates feature flag and unused code

[aaemnnosttv]

Feature Description

Once the zeroDataStates feature is complete and rolled out to 100% of eligible sites, we can safely remove the feature flag and remove the old code that no longer runs.

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Do not alter or remove anything below. The following sections will be managed by moderators only.

Acceptance criteria

• All usage of zeroDataStates feature flag should be removed, and any code that runs when zeroDataStates === false should be removed.

Implementation Brief

• Remove zeroDataStates from feature-flags.json
• Search for the zeroDataStates string within the code base and review code where it is present. Any logic/component which was rendered conditionally when the zeroDataStates feature was enabled should be rendered unconditionally now. Any code which was rendered when the feature flag was disabled should be removed.
• Use of the useFeature hook with zeroDataStates as a parameter should be removed.
• Review stories where the zeroDataStates feature is enabled via the story's parameters to remove the parameter.
  • Legacy Gathering data stories must be removed.

Test Coverage

• Update VRT images and E2E tests if necessary.

QA Brief

• Set up a site with forced zero data for modules
• Ensure that this branch doesn't differ from the released plugin
• Ensure that no new warnings are raised in the console
• Check that the zeroDataStates feature flag is gone from the tester plugin as well

Changelog entry

[FlicHollis]

Hi @techanvil and @aaemnnosttv just checking if this is still blocked and that @techanvil is still planning on working on this?

[techanvil]

@FlicHollis this one is still blocked, pending the execution of 5047. I was still planning on working on the IB, as I did the IB for 5047 and the process will be something of a continuation, but someone else could do it too.

[FlicHollis]

That makes sense - thanks @techanvil

[eugene-manuilov]

IB ✔️

[mohitwp]

QA Update ❌

@makiost

I found few issues :

Issue 1: Bracket ) character in the ‘All Traffic’ widget on develop branch. Evan confirmed that it is due to this PR.

Issue 2: Notices for gathering and zero state are no longer appearing on develop branch.

https://user-images.githubusercontent.com/94359491/188116654-c7bfa24e-c9e0-430a-8100-ffbef164fd49.mp4

https://user-images.githubusercontent.com/94359491/188116703-0b1dc6ed-c7fe-410a-9b31-a959e299c585.mp4

[maciejost]

@mohitwp Addressed the issues you pointed out in a new pr 👍

[aaemnnosttv]

@makiost is this ready for review again? I see it's still with you in Execution.

[maciejost]

@aaemnnosttv All the fixes from QA are done, I just need to update one E2E test for it to be complete. Since the gathering data notifications are no longer hidden behind a feature flag, the notifications test fails, due to the gathering data notification being showed instead of the expected test notification.

[mohitwp]

QA Update ✅

Verified

• Verified for the site which is in default gathering state.
• Verified for the site which is in forced gathering or zero state.
• Verified on main branch.
• On main branch 'Zero data state' feature flag not showing under tester plugin and zero data both state 'gathering and zero' working fine.
• No console errors.
• Also, CTA for both gathering and zero data state are now appearing.
• CTA appearing on both main,entity and WP dashboard.