seastar: fix makecheck error: missing 'typename'

update seastar submodule to wip-matanb-seastar-july4
Reverting https://github.com/scylladb/seastar/commit/8a3dc425dd9bff7a00ffa3345768e01b1a24825f

This revert is pushed to not block all other PRs that are failing make
check due to this.

Fixes: https://tracker.ceph.com/issues/66834
Signed-off-by: Matan Breizman <mbreizma@redhat.com>
(cherry picked from commit 52ec2a37830a53770546a356fa837a1f41b6e44d)

diff --git a/src/seastar b/src/seastar
index 09a44e0d403a97db696837e75b4b61f592baf35b..96a93ba0cf2d1013914aea203488d2c0cccc54c6 160000 (submodule)
--- a/src/seastar
+++ b/src/seastar
@@ -1 +1 @@
-Subproject commit 09a44e0d403a97db696837e75b4b61f592baf35b
+Subproject commit 96a93ba0cf2d1013914aea203488d2c0cccc54c6