Permit filter work item widgets by type on GraphQL

Currently, every time we load a work item and select any widget data we
load all the widgets related to that work item, even if we don't want to
use all every widget related to the WorkItem.

To avoid that, we're introducing two possible ways to filter the widgets
of a work item:
- types_except: where we list widget types that we don't want on the
  result. This might be useful on places where we want all the Widgets
  except one or two, like on the main WorkItem UI, where we load the
  notes widget after loading the whole work item.
- types_in: where we list only the widget types desired on the result.
  This might be useful as the secong query on the main WorkItem UI,
  where we want to load just the notes for the WorkItem, or on WorkItems
  lists where we usually just want to list a small set of widgets.

Related to: https://gitlab.com/gitlab-org/gitlab/-/issues/521310
Changelog: changed