Apply no-buffer-constructor lint rule

lib/common.js

@@ -34,7 +34,7 @@ function generateDeviceId(deviceIdStruct) {
   // Escapes everything except alphanumerics and underscore
   function esc(str) {
     return str.replace(/[^A-Za-z0-9_]/g, chr => {
-      const buf = new Buffer(chr, "utf8");
+      const buf = Buffer.from(chr, "utf8");
       let rep = "";
       for (let b of buf) rep += "%" + b.toString(16).toUpperCase();
       return rep;