Update dependency @elastic/request-converter to v8.18.0 (#2642)

Co-authored-by: elastic-renovate-prod[bot] <174716857+elastic-renovate-prod[bot]@users.noreply.github.com>
Co-authored-by: Josh Mock <joshua.mock@elastic.co>

Author: elastic-renovate-prod[bot]

package.json

@@ -56,7 +56,7 @@
     "node": ">=18"
   },
   "devDependencies": {
-    "@elastic/request-converter": "8.17.0",
+    "@elastic/request-converter": "8.18.0",
     "@sinonjs/fake-timers": "14.0.0",
     "@types/debug": "4.1.12",
     "@types/ms": "0.7.34",