BUG #18741: Detaching a partition referencing a partitioned table fails with a trigger-related error

The following bug has been logged on the website:

Bug reference:      18741
Logged by:          Alexander Lakhin
Email address:      exclusion@gmail.com
PostgreSQL version: 17.2
Operating system:   Ubuntu 22.04
Description:

The following script:
CREATE TABLE pt1 (a int PRIMARY KEY) PARTITION BY RANGE (a);
CREATE TABLE p1 PARTITION OF pt1 FOR VALUES FROM (0) TO (1);

CREATE TABLE pt2 (a int) PARTITION BY RANGE (a);
CREATE TABLE p2 (a int, FOREIGN KEY (a) REFERENCES pt1);

ALTER TABLE pt2 ATTACH PARTITION p2 FOR VALUES FROM (0) TO (1);
ALTER TABLE pt2 DETACH PARTITION p2;

fails with:
ERROR:  XX000: could not find ON INSERT check triggers of foreign key
constraint 16404
LOCATION:  GetForeignKeyCheckTriggers, tablecmds.c:11355

Reproduced on REL_15_STABLE (starting from f4566345c) .. master.