Upgrade explorer cardano-node with conway support (#1550)

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* [x] CHANGELOG updated or not needed
* [x] Documentation updated or not needed
* [x] Haddocks updated or not needed
* [x] No new TODOs introduced or explained herafter

.github/workflows/explorer/docker-compose.yaml

@@ -2,7 +2,7 @@ version: "3.9"
 
 services:
   cardano-node:
-    image: ghcr.io/intersectmbo/cardano-node:9.0.0
+    image: ghcr.io/intersectmbo/cardano-node:9.1.0
     volumes:
       - /srv/var/cardano/state-preview:/data
     environment: