Update seastar submodule
Update seastar submodule

* seastar 5eaec672a2...95f4277c16 (1):
  > Merge "Add an option for making sstring an alias to std::string" from Rafael

avikivity/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla,scylladb/scylla,avikivity/scylla,avikivity/scylla