Fix ESLint issues: prefer-const warnings and missing semicolons

Co-authored-by: oschwartz10612 <4999704+oschwartz10612@users.noreply.github.com>

server/lib/rateLimitStore.ts

@@ -1,6 +1,6 @@
 import { MemoryStore, Store } from "express-rate-limit";
 
 export function createStore(): Store {
-    let rateLimitStore: Store = new MemoryStore();
+    const rateLimitStore: Store = new MemoryStore();
     return rateLimitStore;
 }