docs: Add link in detect-new-buffer docs

Author: nzakas

docs/rules/detect-new-buffer.md

@@ -3,3 +3,7 @@
 ⚠️ This rule _warns_ in the ✅ `recommended` config.
 
 <!-- end auto-generated rule header -->
+
+`new Buffer()` now emits a deprecation warning in Node.js.
+
+More information: [new Buffer(number) is unsafe](https://github.com/nodejs/node/issues/4660)