SSISDB user "AllSchemaOwner" is not SQL Server Login
Finally found an answer:
You can create database user, which won't have a SQL Login and won't be able to authenticate, but will have permissions and can be specified in WITH EXECUTE AS clause for stored procedures and functions.

The simple way to create such a user is just to use clause WITHOUT LOGIN during user creation:

Use SSISDB;
GO
CREATE USER 'AllSchemaOwner' WITHOUT LOGIN;
GO