Improved sorting of config which exists already on the site

Problem/Motivation

Sorting of config is not easy from contrib. But we need to sort the config so that when an import happens no unnecessary diff is shown.

See #3230826: Expose API to sort arbitrary config arrays: TypedConfigManager::getCanonicalRepresentation() should override its parent and their sub-issues.

Steps to reproduce

Export config
create a split and partially split something
edit that something
export the config
attempt to import it again (this should be a clean import as we just exported it and didn't change anything in the mean time.

Proposed resolution

Use the active config as a model to sort.

Remaining tasks

do it

User interface changes

none, less diffs

API changes

none

Data model changes

none