chore: remove deprecated Telegram support group link (#780)

Removed depredated Telegram support group link - the group has been deprecated earlier this year

docs/reference/troubleshooting/docs-contribution/docs.md

@@ -13,7 +13,7 @@ Contributing to any large project necessitates collaboration among project membe
 
 As collaboration on contribution to zkSync documentation is such an integral part of the community, there are many ways to communicate with others doing the same and to learn from them:
 
-- Instant messaging tools, such as [zkSync Discord](https://join.zksync.dev/), [Telegram: user support group](https://t.me/zksync_support).
+- Instant messaging tool, such as [zkSync Discord](https://join.zksync.dev/).
 - Issues - Communicate about actionable items (things that can be acted upon and completed, such as problems with a specific Documentation page, a need for reorganization, etc.):
   - If you find a problem with a specific page in the zkSync documentation, you can always [edit the page](#edit-or-review-a-documentation-page) to fix it.
   - If you want to discuss a larger problem or propose a major change to the zkSync documentation, you can raise an [issue on Github](https://github.com/matter-labs/zksync-web-v2-docs/issues).