Update dependency @elastic/request-converter to v9.1.2

Author: elastic-renovate-prod[bot]

package.json

@@ -58,7 +58,7 @@
     "node": ">=18"
   },
   "devDependencies": {
-    "@elastic/request-converter": "9.1.1",
+    "@elastic/request-converter": "9.1.2",
     "@sinonjs/fake-timers": "14.0.0",
     "@types/debug": "4.1.12",
     "@types/ms": "2.1.0",