Update VSCode Typescript version setting (#43131)

This PR updates VSCode settings to use Fleet's installed version of
Typescript (v4.7.4) for its language server (linting, autocomplete,
etc.) instead of what's built in to VSCode (v6.0.2). As the two can
drift, we end up with VSCode incorrectly highlighting certain syntax as
incorrect.

.vscode/settings.json

@@ -37,5 +37,6 @@
     "prettier.requireConfig": true,
     "yaml.schemas": {
         "https://json.schemastore.org/codecov.json": ".github/workflows/codecov.yml"
-    }
+    },
+    "js/ts.tsdk.path": "node_modules/typescript/lib"
 }