Language identifiers page is missing metadata

[gilmoreorless]

I noticed the page at https://code.visualstudio.com/docs/languages/identifiers is missing a page title. Looking at the source file, it has no metadata at all, unlike every other page in that directory.
I'd create a PR to add the metadata, but I don't know what to put there... 😃

[gregvanl]

Thanks, will fix.