Change config schema type to mapping (D10.3 compat)

Problem/Motivation

We are running ZoomAPI module, which leverages APITools. Running database updates on D10.3.2 throws the an error.

>  [notice] Update started: system_post_update_add_langcode_to_all_translatable_config
>  [error]  AssertionError: Failed on config name 'apitools.client.zoomapi' in assert() (line 264 of /var/www/html/web/core/modules/system/system.post_update.php) #0 /var/www/html/web/core/modules/system/system.post_update.php(264): assert()

The assertion is

    // Simple config is always a mapping.
    assert($typed_config instanceof Mapping, "Failed on config name '$name'");

This seems to be because the APITools schema specifies type sequence when it should be type mapping. Updating the schema fixes the issue for us.

Steps to reproduce

Update to Core 10.3.2

Proposed resolution

Update the config schema type