The creation of JCR workspace - which should be done when adding ad CT definition with
autoCreate: true
fails.

This has been observed on master after 6.3-hackathon in the context of failing functional tests ContentTypeFunctionalTests (see DEV-1975, DEV-1974) .

Now failing ContentTypeFunctionalTests are also reported for the 6.2-branch (e.g. see https://jenkins.magnolia-cms.com/job/platform/job/ce/job/release%252F6.2/29/#showFailuresLink)

You can use the BookShelf app  - used in for ContentTypeFunctionalTests - to reproduce.
=> https://git.magnolia-cms.com/projects/PLATFORM/repos/ce/browse/magnolia-integration-tests/tests/src/test/resources/bookshelf 

Add 1st CT then app as file-based resources - or see what happens in ContentTypeFunctionalTests - but that's maybe harder to debug
-----------------
Result after discovery :
Waiting for the "restore the file-system/resource-origin observation" in DX Core 6.3