docs(readme): add notice about hacktoberfest (#4491)

* docs(readme): add notice about hacktoberfest

* dev

---------

Co-authored-by: Alexandr <qwerty541zxc@gmail.com>

backend/readme.md

@@ -99,6 +99,9 @@
 
 # Important Notices <!-- omit in toc -->
 
+> [!IMPORTANT]\
+> Please note that we are NOT participating in Hacktoberfest this year. Unfortunately, the only person with sufficient access rights to remove the repository label is currently unreachable, so we are notifying you here. As a small team, we cannot handle the increased volume of PRs and issues that the event brings. We appreciate your understanding.
+
 > [!IMPORTANT]\
 > Since the GitHub API only [allows 5k requests per hour per user account](https://docs.github.com/en/graphql/overview/resource-limitations), the public Vercel instance hosted on `https://github-readme-stats-phi-jet-58.vercel.app/api` could possibly hit the rate limiter (see [#1471](https://github.com/anuraghazra/github-readme-stats/issues/1471)). We use caching to prevent this from happening (see https://github.com/anuraghazra/github-readme-stats#common-options). You can turn off these rate limit protections by deploying [your own Vercel instance](#disable-rate-limit-protections).