Enable clippy::eq_op (#9369)

This PR enables the
[`clippy::eq_op`](https://rust-lang.github.io/rust-clippy/master/index.html#/eq_op)
rule and fixes the outstanding violations.

Enabling this rule seems to have caught two bugs!

Release Notes:

- N/A

crates/workspace/src/workspace.rs

@@ -2663,7 +2663,7 @@ impl Workspace {
         if self
             .follower_states
             .values()
-            .all(|state| state.leader_id != state.leader_id)
+            .all(|state| state.leader_id != leader_id)
         {
             let project_id = self.project.read(cx).remote_id();
             let room_id = self.active_call()?.read(cx).room()?.read(cx).id();