Add vote rate limit

package.json

@@ -14,13 +14,14 @@
   "dependencies": {
     "better-sqlite3": "^5.4.3",
     "express": "^4.17.1",
+    "express-rate-limit": "^5.1.3",
     "http": "0.0.0",
     "iso8601-duration": "^1.2.0",
+    "node-fetch": "^2.6.0",
     "redis": "^3.0.2",
     "sync-mysql": "^3.0.1",
     "uuid": "^3.3.2",
-    "youtube-api": "^2.0.10",
-    "node-fetch": "^2.6.0"
+    "youtube-api": "^2.0.10"
   },
   "devDependencies": {
     "mocha": "^7.1.1",