Describe the bug

mpsc_pbuf_concurrent test fails on unrelated PR randomly.

Some CI reports:

https://github.com/zephyrproject-rtos/zephyr/actions/runs/4293444748/jobs/7481169859 (PR #55225)
https://github.com/zephyrproject-rtos/zephyr/actions/runs/4555021284/jobs/8033743709 (PR #56321)

To reproduce

I don't know, it's a random behavior.

Expected behavior

The test should not fail.

Impact

PR can be blocked by this test failing on the CI.

Logs and console output

See the linked CI reports.

Environment

Latest CI environment.