Update the documented triple Mustache tag allowlist (#37083)
Update the documented triple Mustache tag allowlist (#37083)

It's currently out of sync with the code. It also incorrectly states
that amp-list is allowed (it's not). That's probably a typo from #31300.

https://github.com/ampproject/amphtml/blob/c91e704e4d09d8fbac1068653e0dd71a078d8912/src/purifier/sanitation.js#L104-L159
media-net/amphtml,jpettitt/amphtml,mhc-gh/amphtml,ampproject/amphtml,ampproject/amphtml,Gregable/amphtml,alanorozco/amphtml,alanorozco/amphtml,jpettitt/amphtml,media-net/amphtml,alanorozco/amphtml,ampproject/amphtml,jpettitt/amphtml,mhc-gh/amphtml,alanorozco/amphtml,Gregable/amphtml,Gregable/amphtml,media-net/amphtml,Gregable/amphtml,jpettitt/amphtml,mhc-gh/amphtml,danielrozenberg/amphtml,Gregable/amphtml,mhc-gh/amphtml,media-net/amphtml,ampproject/amphtml,alanorozco/amphtml,danielrozenberg/amphtml,Gregable/amphtml,danielrozenberg/amphtml,Gregable/amphtml,ampproject/amphtml,mhc-gh/amphtml,jpettitt/amphtml,media-net/amphtml,mhc-gh/amphtml,alanorozco/amphtml,jpettitt/amphtml,alanorozco/amphtml,ampproject/amphtml,danielrozenberg/amphtml,ampproject/amphtml,ampproject/amphtml,danielrozenberg/amphtml,mhc-gh/amphtml,danielrozenberg/amphtml,media-net/amphtml,danielrozenberg/amphtml,alanorozco/amphtml,mhc-gh/amphtml,jpettitt/amphtml,media-net/amphtml,Gregable/amphtml,media-net/amphtml,jpettitt/amphtml,danielrozenberg/amphtml