bump @types/node to 18

Do this to match `process.versions.node` as indicated inside of Texts (as of
writing), so types correspond to the runtime that is actually used.

package.json

@@ -29,7 +29,7 @@
     "@types/eslint": "^8.4.10",
     "@types/jest": "^27.4.1",
     "@types/lodash": "^4.14.181",
-    "@types/node": "^16.7.10",
+    "@types/node": "^18.17.1",
     "@types/ws": "^7.4.7",
     "eslint": "^8.30.0",
     "jest": "^27.5.1",

src/websocket/wsclient.ts

@@ -35,7 +35,7 @@ class WSClient {
 
   private lastSequenceNumber?: number
 
-  private heartbeatTimer?: NodeJS.Timer
+  private heartbeatTimer?: NodeJS.Timeout
 
   private heartbeatTimeout?: NodeJS.Timeout
 

yarn.lock

@@ -2074,7 +2074,7 @@ __metadata:
     "@types/eslint": ^8.4.10
     "@types/jest": ^27.4.1
     "@types/lodash": ^4.14.181
-    "@types/node": ^16.7.10
+    "@types/node": ^18.17.1
     "@types/ws": ^7.4.7
     discord-api-types: ^0.37.45
     erlpack: ^0.1.4
@@ -2291,10 +2291,12 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@types/node@npm:^16.7.10":
-  version: 16.18.34
-  resolution: "@types/node@npm:16.18.34"
-  checksum: 35c0ffe09687578d002ceb7e706d0ba450546aeb3d2716f28691f2af0063bd274dbde0f741d087ea217f2a8db413eb700d22dfb4f08a67986ff801423bd7be8d
+"@types/node@npm:^18.17.1":
+  version: 18.19.3
+  resolution: "@types/node@npm:18.19.3"
+  dependencies:
+    undici-types: ~5.26.4
+  checksum: 58c4fa45a78fcec75c78182a4b266395905957633654eb0311c5f9c30ac15c179ea2287ab1af034e46c2db7bb0589ef0000ee64c1de8f568a0aad29eaadb100c
   languageName: node
   linkType: hard
 
@@ -7498,6 +7500,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"undici-types@npm:~5.26.4":
+  version: 5.26.5
+  resolution: "undici-types@npm:5.26.5"
+  checksum: 3192ef6f3fd5df652f2dc1cd782b49d6ff14dc98e5dced492aa8a8c65425227da5da6aafe22523c67f035a272c599bb89cfe803c1db6311e44bed3042fc25487
+  languageName: node
+  linkType: hard
+
 "unicode-canonical-property-names-ecmascript@npm:^2.0.0":
   version: 2.0.0
   resolution: "unicode-canonical-property-names-ecmascript@npm:2.0.0"