Add a note to set the website URL in the Mailchimp Audience settings.

[iamdharmesh]

Description of the Change

As reported in #91 and #92, the "« return to our website" button could lead to a 404 error from the subscribe/unsubscribe confirmation page if the website URL is not set in the Mailchimp Audience settings.

This PR adds a note under the "List Options" section, instructing users to set the website URL in the Mailchimp Audience settings to prevent 404 errors and ensure users can return to the website without any issues.

Closes #91
Closes #92

How to test the Change

• Verify that the note is shown under the "List Options" section of the settings.

Changelog Entry

Added - A note advising users to set the website URL in the Mailchimp Audience settings.

Credits

Props @MaxwellGarceau @dkotter @iamdharmesh

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.

[qasumitbagthariya]

QA Update ✅

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I have verified this PR in the fix/92 branch, which has been fixed and is functioning as intended.

I tested the following on this branch:

• Note is shown under the "List Options" section of the settings.

Testing Environment

Details

• WordPress: 6.8
• Theme: Twenty Twenty-Four 1.3
• PHP: 8.0.30
• Web Server: Nginx 1.20.2
• Browser: Chrome
• OS: macOS 15.2
• Branch: smoke-testing

Steps to Test- As mentioned in the PR description.
Test Results - It is working as expected.
Functional Demo / Screencast -
Special Notes - Ready for UAT
Testing Document status:
Cases related to this Issue/PR are added to the Critical Flow Wiki pages:

• Yes - pending
• Not Required/Applicable for this PR

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Noted: I tried adding the website URL, but it threw an error from Mailchimp's side. However, the PR notice looks good overall.

[qasumitbagthariya]

Regression / Smoke Test Report ✅

Tested with the smoke-testing branch, it works as expected, similar to the fix-specific branch.

Testing Environment

Details

• WordPress: 6.8
• Theme: Storefront 4.6.0
• Theme: Twenty Twenty-Four 1.3
• PHP: 8.0.30
• Web Server: Nginx 1.20.2
• Browser: Chrome
• OS: macOS 15.2
• Branch: smoke-testing

Next Step- Ready to Merge 🚀