Add views argument plugin Group Membership Uid for a custom extra Contextual filters for views like Group Content: User is member

Problem/Motivation

#2715011: Missing data_table for Group and GroupContent
#2706495: add Views reverse relationships from entities to Group Content
#2715285: show group memberships on a user account tab
#2813405: Add a field to view and edit content's groups

It was listed by Open Social profile code

  // @todo remove this when this hits https://www.drupal.org/node/2715285.
  // Also note that by default the Group Creator is a Member now, that's
  // where we check on in Drupal\social_group\Plugin\views\argument\UserUid.php.

Steps to reproduce

When we create a view to list groups which the user is a member of them for the current viewing user

Proposed resolution

Have a custom extra Contextual filters views argument plugin

Remaining tasks

Copy the custom plugin with custom changes from Open Social profile code and have that in Vardoc

User interface changes

API changes

Alter view's query when used

Data model changes

Only filter by user