[renovate] Update rabbitmq Docker tag to v4

This MR contains the following updates:

Package	Update	Change
rabbitmq	major	3-management -> 4-management

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integration-tests/docker-compose.yml

@@ -99,7 +99,7 @@ services:
       MONGO_INITDB_ROOT_PASSWORD: example
 
   rabbitmq:
-    image: rabbitmq:3-management
+    image: rabbitmq:4-management
 
   routing-app:
     image: registry.code.fbi.h-da.de/demoquandt/qkdn-controller/routing-app:qkdn-main