fix: deprecate from "new Buffer" to "Buffer.from" (#6489)

src/core/utils.js

@@ -623,7 +623,7 @@ export const btoa = (str) => {
   if (str instanceof Buffer) {
     buffer = str
   } else {
-    buffer = new Buffer(str.toString(), "utf-8")
+    buffer = Buffer.from(str.toString(), "utf-8")
   }
 
   return buffer.toString("base64")