fix for master branch leading to legacy

Author: lindseymoore

config/redirects

@@ -7,6 +7,7 @@ symlink: upcoming -> master
 
 raw: ${prefix}/ -> ${base}/current/
 raw: ${prefix}/stable -> ${base}/current/
+raw: ${prefix}/master -> ${base}/upcoming/
 
 [*-master]: ${prefix}/${version}/fundamentals/crud/read-operations/watch/ -> ${base}/${version}/fundamentals/crud/read-operations/changestream/
 [*-master]: ${prefix}/${version}/usage-examples/watch/ -> ${base}/${version}/usage-examples/changestream/