[FEATURE]: Unhook default shortlink tag

[vancoder]

Description

By default, WP creates a link tag in all posts for the default shortlink, eg:
<link rel='shortlink' href='https://www.kauffman.org/?p=12913' />

However, the URL it uses only works for the standard post post type. In all other cases that link will lead to a 404.

The same link is also included in the HTTP header.

These should be removed.

Sample code.

Use Case

Services that validate links within posts should not be hitting dysfunctional shortlinks.

Acceptance Criteria

• Add a feature to remove the default shortlink behavior.
• Verify removal via a test.