LDEV-3514: Use postInterceptor instead of preInterceptor.
PreInterceptor apparently runs before Hibernate transaction gets created. When an exception in the proxied method occurs, the transaction is canceled and is not re-created when retry is attempted. This leads to "no session" or "read only transaction on write" errors.
PostInterceptor seems to work when the transaction is already created, so retries happen witin its scope.
