fix(deps): update dependency prom-client to v15

Author: renovate[bot]

package.json

@@ -124,7 +124,7 @@
     "pino-pretty": "^11.2.2",
     "poolifier": "^4.2.10",
     "preview-email": "^3.1.0",
-    "prom-client": "^14.2.0",
+    "prom-client": "^15.1.3",
     "qrcode": "^1.5.4",
     "reflect-metadata": "0.2.2",
     "rxjs": "^7.8.1",