(dev/core#4641) ListUnsubscribe - Fix HTTP URL generation on WordPress

[totten]

Overview

Follow-up to recent #28964. This fixes an issue with generating the unsubscribe URL on WordPress.

Before

If I execute the mailing job via CLI:

cv api -U admin job.process_mailing

Then the resulting email has List-Unsubscribe which points to the WP backend, e.g.

http://wpmaster.127.0.0.1.nip.io:8001/wp-admin/admin.php?page=CiviCRM&q=civicrm%2Fmailing%2Funsubscribe&reset=1&jid=4&qid=25&h=77jhhesmltetm6uk

This URL doesn't actually work for purposes of HTTP One-Click.

After

The resulting email has List-Unsubscribe which points to the WP frontend. Depending on whether clean URL support is active, this can be either:

http://wpmaster.127.0.0.1.nip.io:8001/civicrm/?civiwp=CiviCRM&q=civicrm%2Fmailing%2Funsubscribe&reset=1&jid=3&qid=28&h=o9qdzkepvkuvwkoo

or

http://wpmaster.127.0.0.1.nip.io:8001/civicrm/mailing/unsubscribe/?reset=1&jid=3&qid=28&h=o9qdzkepvkuvwkoo

Either style works for purposes of HTTP One-Click.

[civibot]

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