Update the article to reflect that it is simpler now to do it by running the following command:
npm install --save-dev @types/jquery
Maybe write a new, shorter, one and update the old one with a link to the new one.
See also Typings and Automatic Type Acquisition for more information about how VS Code does it for us nowadays.
Note: that article is written in both French and English.
Link: https://www.forevolve.com/en/articles/2016/08/12/how-to-add-jquery-intellisense-to-a-visual-studio-code-javascript-file/