Update docker.io/library/redis Docker tag to v8

Also see:
https://github.com/TwiN/gatus?tab=readme-ov-file#storage

resources/chaosknoten/tickets/docker_compose/compose.yaml.j2

@@ -13,7 +13,7 @@ services:
     restart: unless-stopped
 
   redis:
-    image: docker.io/library/redis:7.4.7
+    image: docker.io/library/redis:8.4.0
     ports:
       - "6379:6379"
     volumes:

resources/external/status/docker_compose/config/general.yaml

@@ -1,6 +1,8 @@
 storage:
   type: postgres
   path: "postgres://${POSTGRES_USER}:${POSTGRES_PASSWORD}@database:5432/${POSTGRES_DB}?sslmode=disable"
+  maximum-number-of-results: 240 # Default are 100. 240 are 4h for 1m interval checks.
+  maximum-number-of-events: 1000 # Default are 50. Let's keep a long history here - 1000 should suffice for a year with around 3 events a day.
 
 ui:
   title: CCCHH Status