As it turns out, a donut cannot just still one's hunger, but also provide valuable information on the release date of one of the most anticipated games of the year. The timely nature of this probably intentional reveal suggests that Microsoft intends to heavily promote the game ahead of its beta launch this week.
https://www.notebookcheck.net/Halo-Infinite-s-release-month-has-apparently-been-revealed-by-an-advertisement-for-a-donut.552746.0.html