message: hot restarter: Log errno for 'panic: cannot open shared memory' error
  The error message right now assumes that the errno is EACCESS which
  isn't necessarily true. Logging the errno makes this easier to debug.
diff: @@ -57,7 +57,8 @@ SharedMemory& SharedMemory::initialize(uint64_t stats_set_size, Options& options
  int shmem_fd = os_sys_calls.shmOpen(shmem_name.c_str(), flags, S_IRUSR | S_IWUSR);
  if (shmem_fd == -1) {
  - PANIC(fmt::format("cannot open shared memory region {} check user permissions", shmem_name));
  + PANIC(fmt::format("cannot open shared memory region {} check user permissions. Error: {}",
  + shmem_name, strerror(errno)));
  }
  if (options.restartEpoch() == 0) {
  