Update prom/prometheus Docker tag to v2.38.0

Author: renovate[bot]

.circleci/config.yml

@@ -4,7 +4,7 @@ jobs:
   test:
     docker:
       - image: web3f/node:v0.1.3
-      - image: prom/prometheus:v2.36.2
+      - image: prom/prometheus:v2.38.0
         name: prometheus
     steps:
       - checkout