unstable regress tests modules/injection_points/syscache-update-pruned

Hi

Itested my older patch for session variables with dedicated system catalog,
and I was surprised so one independent test fails

src/test/modules/injection_points/expected/syscache-update-pruned.out

you can apply attached patch, and run test

# using temp instance on port 58928 with PID 422150
ok 1 - basic 82 ms
ok 2 - inplace 1556 ms
not ok 3 - syscache-update-pruned 719 ms
ok 4 - heap_lock_update 157 ms
1..4
# 1 of 4 tests failed.

pavel(at)nemesis:~/src/postgresql$ cat
/home/pavel/src/postgresql/src/test/modules/injection_points/output_iso/regression.diffs
diff -U3
/home/pavel/src/postgresql/src/test/modules/injection_points/expected/syscache-update-pruned.out
/home/pavel/src/postgresql/src/test/modules/injection_points/output_iso/results/syscache-update-pruned.out
---
/home/pavel/src/postgresql/src/test/modules/injection_points/expected/syscache-update-pruned.out
2026-02-19 05:31:42.352060555 +0100
+++
/home/pavel/src/postgresql/src/test/modules/injection_points/output_iso/results/syscache-update-pruned.out
2026-03-09 06:50:54.521741837 +0100
@@ -75,6 +75,7 @@
SELECT FROM injection_points_wakeup('heap_update-before-pin');
<waiting ...>
step grant1: <... completed>
+ERROR: tuple concurrently deleted
step wakegrant4: <... completed>
step inspect4:
SELECT relhastriggers, relhassubclass FROM pg_class
@@ -82,6 +83,6 @@

relhastriggers|relhassubclass
--------------+--------------
-f |f
+t |t
(1 row)

Regards

Pavel