Add data for MathML global attributes (#16995)
Add data for MathML global attributes (#16995)

* Add data for MathML global attributes

This is adding data for new pages added in
https://github.com/mdn/content/pull/17812

* improve version_added for firefox & webkit

* update safari version_added ; add dir attribute
mdn/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data