Table partition with primary key in 11.3

CREATE TABLE public.test1 (
     x1 integer NOT NULL,
     x2 integer NOT NULL,
     CONSTRAINT test1_pkey PRIMARY KEY (x1) INCLUDE(x2)
) PARTITION BY RANGE (x2);

This query works in 11.1 but fails in 11.3 with messages:

ERROR: insufficient columns in PRIMARY KEY constraint definition
DETAIL: PRIMARY KEY constraint on table "test1" lacks column "x2" which 
is part of the partition key.
SQL state: 0A000