qa/tasks/mgr: test_module_selftest set influx hostname to avoid warnings

self-test will hit error MGR_INFLUX_NO_SERVER since we dont have
hostname configed, the following command will add a test hostname
so the error won't appear and fail the test.

Fixes: https://tracker.ceph.com/issues/72747
Signed-off-by: Nitzan Mordechai <nmordec@ibm.com>

Merge pull request #66149 from amathuria/wip-amat-update-seastar-nov25

seastar: bump up seastar submodule

Reviewed-by: Matan Breizman <mbreizma@redhat.com>