Remove the TemplateLink macro from MDN source

[hamishwillee]

The macro {{TemplateLink}} is used in MDN source to create a link to the source for a particular macro.

It is used approximately 28 times in 12 files in US-eng source. Given that we want to reduce macro use and there is no particular reason for it not to just be a link, propose we first delete it from source and then remove the macro altogether.

Is there a way to force removal from translations too?

Suggested by @teoli2003 in #9904 (review)

[hamishwillee]

This is fixed by the linked PRs. When those merged will propose Yari PR to remove the template.

[hamishwillee]

Closing as all the work done. I opened request in Yari for removal of the template mdn/yari#4848