Alert Label is not available as token to Twig

Problem/Motivation

Individual Site Alerts lack a dedicated "headline" field. While the module makes available a WYSIWYG field for the alert message and a headline can be created within that, it can be useful to have a dedicated "headline" field for alerts, particularly if site administrators wanted to restrict text formats available to editors creating these alerts. The Label field could be made use of for this purpose.

Proposed resolution

This patch proposes adding the value of the Label to the Twig build array so that it's available as an optional token for use in the Twig template if desired.

Remaining tasks

None.

User interface changes

None.

API changes

alert.label is available as a Twig token for use in the alert template.

Data model changes

None.