chore: Bump Rust edition to 2024 (#27800)

Follow-up to https://github.com/zed-industries/zed/pull/27791

Release Notes:

- N/A

crates/collab/src/llm/db/tests/billing_tests.rs

@@ -1,10 +1,11 @@
 use crate::{
+    Cents,
     db::UserId,
     llm::{
-        db::{queries::providers::ModelParams, LlmDatabase, TokenUsage},
         FREE_TIER_MONTHLY_SPENDING_LIMIT,
+        db::{LlmDatabase, TokenUsage, queries::providers::ModelParams},
     },
-    test_llm_db, Cents,
+    test_llm_db,
 };
 use chrono::{DateTime, Utc};
 use pretty_assertions::assert_eq;