When removed objectrelationlist from CT then relations still exists

Steps to reproduce

1. Install clean eZ Platform 2.5 or IBEXA DXP 3+
2. Add new CT with ezobjectrelationlist field
3. Add the content of type created in step 2 with relation to another content
4. Remove field ezobjectrelationlist from CT
5. Go to content created in step 2 and check the Relations tab

Result
Relations still exist after the field was removed. Reverse relations are shown as well.

Expected result
Relations  should be removed when ezobjectrelationlist field was removed from CT