[Bug] [Doctor] db consistency fix function not working

[6543]

doctor check-db-consistency task use models.DeleteOrphanedObjects() witch does not work

ref: #15658 (comment)

tested with mariadb Ver 15.1

gitea v1.13.7, v1.14.1 & master have same issue:

v13: Error: Unsupported type
v14&master: - [C] Error: %!v(MISSING) whilst deleting orphaned objects

[KN4CK3R]

%!v(MISSING) should be fixed by #15658 and the underlaying bug in models.DeleteOrphanedObjects() gets fixed with #15657.