Problem/Motivation
\Drupal\layout_builder\Section::setComponent should verify the region in that layout exists
Steps to reproduce
Programatically/via config actions, you can set/append/insert a component to a region that doesn't exist in a given layout. No errors given, no UI changes, but the component lives in the section.
Proposed resolution
Verify the layout provides the region on \Drupal\layout_builder\Section::setComponent.
Remaining tasks
Fix + test.
User interface changes
None.
Introduced terminology
None.
API changes
None.
Data model changes
None.
Release notes snippet
None.