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

extensions/amp-mustache/amp-mustache.md

@@ -74,7 +74,7 @@ that among other things, you can't use `amp-mustache` to:
 -   Calculate tag name. E.g. `<{{tagName}}>` is not allowed.
 -   Calculate attribute name. E.g. `<div {{attrName}}=something>` is not allowed.
 
-The output of "triple-mustache" is sanitized to only allow the following tags: `a`, `amp-list`, `b`, `br`, `caption`, `col`, `colgroup`, `code`, `del`, `div`, `em`, `h1`, `h2`, `h3`, `hr`, `i`, `ins`, `li`, `mark`, `ol`, `p`, `q`, `s`, `small`, `span`, `strong`, `sub`, `sup`, `table`, `tbody`, `time`, `td`, `th`, `thead`, `tfoot`, `tr`, `u`, `ul`.
+The output of "triple-mustache" is sanitized to only allow the following tags: `a`, `amp-img`, `article`, `aside`, `b`, `blockquote`, `br`, `caption`, `code`, `col`, `colgroup`, `dd`, `del`, `details`, `div`, `dl`, `dt`, `em`, `figcaption`, `figure`, `footer`, `h1`, `h2`, `h3`, `header`, `hr`, `i`, `ins`, `li`, `main`, `mark`, `nav`, `ol`, `p`, `pre`, `q`, `s`, `section`, `small`, `span`, `strong`, `sub`, `summary`, `sup`, `table`, `tbody`, `td`, `tfoot`, `th`, `thead`, `time`, `tr`, `u`, `ul`.
 
 ### Sanitization