docs(iroh-gossip): fix typo in proto.rs (#1927)

## Description

Typo fix

## Notes & open questions



## Change checklist

- [X] Self-review.
- [X] Documentation updates if relevant.
- [ ] Tests if relevant.

Co-authored-by: Friedel Ziegelmayer <[email protected]>
Co-authored-by: Kasey <[email protected]>
Co-authored-by: Rüdiger Klaehn <[email protected]>

iroh-gossip/src/proto.rs

@@ -16,7 +16,7 @@
 //!
 //! The **membership protocol** ([HyParView][hyparview]) is a cluster protocol where each peer
 //! maintains a partial view of all nodes in the swarm.
-//! A peer joins the swarm for a tooic by connecting to any known peer that is a member of this
+//! A peer joins the swarm for a topic by connecting to any known peer that is a member of this
 //! topic's swarm. Obtaining this initial contact info happens out of band. The peer then sends
 //! a `Join` message to that initial peer. All peers maintain a list of
 //! `active` and `passive` peers. Active peers are those that you maintain active connections to.