doc: add link to doc with social processes

Signed-off-by: Michael Dawson <mdawson@devrus.com>

PR-URL: nodejs#45584
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: mhdawson

doc/contributing/suggesting-social-media-posts.md

@@ -0,0 +1,5 @@
+# Suggesting Social Media Posts
+
+Node.js social media is managed by OpenJS Foundation staff. The processes are
+documented in
+[Node.js Social Amplification Request Guidelines](https://docs.google.com/document/d/1yrYZJ2twrbpUuScbo3rmN_v-Jfv6d2tO74nCT6PcpxI).