Update article.md

[viktor-ulyankin]

1 change) More close to English version and it turns to clearer.

2 change) In English, we should use "of" between words "decoration" and "worker.slow" to understand that "decoration" refers to "worker.slow". However, there is no "of" in English version, so that, they aren't joined. In Russian language we don't have "of" or lacking thereof, so we need to use coma.

https://learn.javascript.ru/call-apply-decorators