Filter settings schema types are incorrect

Problem/Motivation

This is text format schema (removed some parts for readability):

filter.format.*:
  type: config_entity
  mapping:
    name:
      type: required_label
    (...)
    filters:
      type: sequence
      orderby: key
      sequence:
        type: filter

Each filter is of type filter:

filter:
  type: mapping
  mapping:
    id:
      type: string
    (...)
    settings:
      type: filter_settings.[%parent.id]

Each filter's settings is of type filter_settings.<filter_plugin_id>, defaulting to filter_settings.*

But here comes the weirdness: Each filter_settings.<filter_plugin_id> is again of type filter (except filter_settings.* which correctly goes to a sequence)

For instance:

filter_settings.filter_html:
  type: filter
  mapping:
    ...

I think each filter_settings.<filter_plugin_id> should be of type mapping

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes

Release notes snippet