galera MDEV-38920 tests skip on galera 26.4.28, gate requires 26.4.29

Two galera MTR tests check the installed galera library version with check_galera_version.inc before they run:

• mysql-test/suite/galera/t/MDEV-38920-evs-config-warn.test
• mysql-test/suite/galera/t/MDEV-38920-install-timer-expired.test

Both set --let $galera_version=26.4.29. On a host with galera 26.4.28, check_galera_version.inc skips both tests with "needs galera >= 26.4.29". Neither test runs, so neither checks the MDEV-38920 fix on that host.

Locally, lowering the gate to --let $galera_version=26.4.28 in both files makes both tests run against the installed 26.4.28 provider, and both pass.

• MDEV-38920-evs-config-warn.test: a single run passes. The test checks that the provider logs two EVS misconfiguration warnings and the cluster still comes up. A repeated run with no server restart between repeats does not find the warning again, because the warning is a one-time startup log line, not a cluster state; that is a property of the test, not a bug in it.
• MDEV-38920-install-timer-expired.test: a full run (4 nodes, SIGSTOP-based fault injection, about 158 seconds) completes and passes.

Please confirm whether the behaviour these two tests check needs galera 26.4.29, or is already present in 26.4.28. If 26.4.28 is enough, lower the gate in both files to --let $galera_version=26.4.28. If 26.4.29 is needed, the test environment's galera library needs that version, so the existing gate does its job.

Until this is resolved, any CI run on galera 26.4.28 skips both tests and gives no coverage of the MDEV-38920 fix.