Address @todo-comment linking to closed issue in feed-icon.html.twig

Problem/Motivation

In #3123832: [META] Fix @todo items referencing closed issues we discovered that there is a @todo in core/themes/olivero/templates/misc/feed-icon.html.twig which references a d.o. issue that is already closed: #3156244: Title variable isn't set by Syndicate block - so the link text is an unfinished sentence.

Here's the @todo:

{#
  @todo - This works around https://www.drupal.org/project/drupal/issues/3156244,
  Title variable isn't set by Syndicate block.
 #}
{% if title is not defined or title is null %}
  {% set title = 'RSS Feed'|t %}
{% endif %}

Steps to reproduce

Proposed resolution

After #3156244: Title variable isn't set by Syndicate block - so the link text is an unfinished sentence landed the title of the syndicate block is taken from config: system.site.name.

Which implies to me, that if the title is empty now, it was done on purpose and that an empty title should be honoured.
Which means we should delete the whole Twig code block together with the @todo.

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet