Hi @nurlan,
i tried with your configurations and everythings seems to work properly, please refer to my liquibase properties:
changeLogFile: db/postgres/liquibase-changeLog.xml
driver: org.postgresql.Driver
url: jdbc:postgresql://localhost:5432/app_ref
username: postgres
password: postgres
classpath: driver: oracle.jdbc.OracleDriver
referenceUrl: jdbc:postgresql://localhost:5432/app
diffChangeLogFile: db/postgres/liquibase-changeLog-ref.xml
referenceDriver: org.postgresql.Driver
referenceUsername: postgres
referencePassword: postgres