Removing duplicated instead word (#30442)
Removing duplicated instead word (#30442)

Just removing the duplicated use of `instead` on `next.config.js/rewrites`  doc

azukaru/next.js,JeromeFitz/next.js,zeit/next.js,azukaru/next.js,JeromeFitz/next.js,JeromeFitz/next.js,zeit/next.js,azukaru/next.js,JeromeFitz/next.js,zeit/next.js,azukaru/next.js