Remove info about patch naming convention in issue template

Problem/Motivation

You get this message, when you create a new issue:

But Drupal has switched to GitLab MR based workflow, so the patch format sentence can be removed.

Also, the HTML sections from the issue template page are already included, so do we need to show a link to the "Issue Summary Template" page?

The video link is also dead ...

Steps to reproduce

Create an issue, and see that there is:

1. A link to the Issue Summary Template → page, but the HTML and headers are already included in the "Issue summary" field right below
2. Patch info, though it has been phased out.
3. Linked to video, but it's a dead URL

Proposed resolution

Decide if the entire info block should be remove, or some elements should stay?

1. Remove patch format info
2. Remove Link to the Issue Summary Template → page?
3. Remove link to video?

Remaining tasks

User interface changes

API changes

Data model changes