Add strict next head handling (#47938)
This adds an `experimental.strictNextHead` flag to allow updating head
tags tracking for pages to resolve the issue with runtime scripts being
appended to the head element breaking the head tracking.
Fixes: https://github.com/vercel/next.js/issues/11012
Fixes: https://github.com/vercel/next.js/issues/20682
x-ref: [slack
thread](https://vercel.slack.com/archives/C051B8JAPQ9/p1680156608831939)
