message: Fix the unit test failure on Mac
  * Fix the unit test failure on Mac
  /proc/self/stat does not exist on Mac because of which mem_str
  was an empty string being fed to stol resulting in the
  invalid_argument error
diff: @@ -255,6 +255,7 @@ void MemoryProfile(long& vm_usage, long& resident_set) {
  std::ifstream ifs("/proc/self/stat", std::ios_base::in);
  std::string mem_in;
  getline(ifs, mem_in);
  + if (mem_in != "") {
  vector<string> mem_str = ng::split(mem_in, ' ');
  vsize = std::stol(mem_str[22]);
  rss = std::stol(mem_str[23]);
  @@ -263,6 +264,7 @@ void MemoryProfile(long& vm_usage, long& resident_set) {
  1024; // in case x86-64 is configured to use 2MB pages
  vm_usage = vsize / 1024; // unit kb
  resident_set = rss * page_size_kb;
  + }
  };
  } // namespace ngraph_bridge
  