Context

Yoast adds the {@see WPSEO_Register_Capabilities::map_meta_cap_for_seo_manager()} filter
before the current user has determined, however, that callback relies on a call to {@see wp_get_current_user}
which will cause an infinite loop if any plugin/theme/custom-code uses {@see user_can()} during the creation of the
user session to determine per-user configurations of sessions.

The correct hook to add the callback would probably be the {@see set_current_user} hook, otherwise
the callback to {@see WPSEO_Register_Capabilities::map_meta_cap_for_seo_manager()} also always receives the user id
which means it would actually also work if {@see user_can()} is called on a user that's not the currently logged in
one, which is pretty common as well.
*

Summary

This PR can be summarized in the following changelog entry:

• Fix bug in capability mapping if current user is no set yet

Relevant technical choices:

• No performance issues, get_user_by_id will always come from the cache for the current logged-in user.
• Also supports non-logged in users now.

Test instructions

Test instructions for the acceptance test before the PR gets merged

This PR can be acceptance tested by following these steps:

Relevant test scenarios

• Changes should be tested with the browser console open
• Changes should be tested on different posts/pages/taxonomies/custom post types/custom taxonomies
• Changes should be tested on different editors (Block/Classic/Elementor/other)
• Changes should be tested on different browsers
• Changes should be tested on multisite

Test instructions for QA when the code is in the RC

• QA should use the same steps as above.

QA can test this PR by following these steps:

Impact check

This PR affects the following parts of the plugin, which may require extra testing:

UI changes

• This PR changes the UI in the plugin. I have added the 'UI change' label to this PR.

Other environments

• This PR also affects Shopify. I have added a changelog entry starting with [shopify-seo], added test instructions for Shopify and attached the Shopify label to this PR.

Documentation

• I have written documentation for this change.

Quality assurance

• I have tested this code to the best of my abilities.
• During testing, I had activated all plugins that Yoast SEO provides integrations for.
• I have added unit tests to verify the code works as intended.
• If any part of the code is behind a feature flag, my test instructions also cover cases where the feature flag is switched off.
• I have written this PR in accordance with my team's definition of done.
• I have checked that the base branch is correctly set.

Innovation

• No innovation project is applicable for this PR.
• This PR falls under an innovation project. I have attached the innovation label.
• I have added my hours to the WBSO document.

Fixes #