* Moved code tag to include new keyword
The new keyword hasn't been explained in the curriculum yet, so have moved the <code> tag to include the new keyword to give a prompt that it needs to be used in the solution.
* Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-arrow-functions-to-write-concise-anonymous-functions.english.md
Added comma.
Co-authored-by: Lasse Jørgensen <28780271+lasjorg@users.noreply.github.com>