include unistd for mac

Author: Jadit19

include/mochios/helpers/client.h

@@ -2,6 +2,7 @@
 
 #include <cstring>
 #include <sstream>
+#include <unistd.h>
 
 #include <brewtils/sys.h>
 #include <brewtils/url.h>
@@ -25,4 +26,4 @@ mochios::message::Response send(mochios::message::Request &request,
 
 } // namespace helpers
 
-} // namespace mochios
+} // namespace mochios