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

They (at least the pretalx one) currently don't work, so try having them
first.

renovate.json

@@ -19,6 +19,16 @@
     "galaxy-roles/**"
   ],
   "packageRules": [
+    {
+      "matchDatasources": ["docker"],
+      "matchPackageNames": ["docker.io/pretix/standalone"],
+      "versioning": "regex:^(?<major>\\d+\\.\\d+)(?:\\.(?<minor>\\d+))$"
+    },
+    {
+      "matchDatasources": ["docker"],
+      "matchPackageNames": ["docker.io/pretalx/standalone"],
+      "versioning": "regex:^v(?<major>\\d+\\.\\d+)(?:\\.(?<minor>\\d+))$"
+    },
     // Create a package rule for grouping all stable non-major dependency updates together.
     // A combination of/inspired by:
     // https://docs.renovatebot.com/presets-group/#groupallnonmajor
@@ -31,16 +41,6 @@
         "minor",
         "patch"
       ]
-    },
-    {
-      "matchDatasources": ["docker"],
-      "matchPackageNames": ["docker.io/pretix/standalone"],
-      "versioning": "regex:^(?<major>\\d+\\.\\d+)(?:\\.(?<minor>\\d+))$"
-    },
-    {
-      "matchDatasources": ["docker"],
-      "matchPackageNames": ["docker.io/pretalx/standalone"],
-      "versioning": "regex:^v(?<major>\\d+\\.\\d+)(?:\\.(?<minor>\\d+))$"
     }
   ],
   "customManagers": [

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:8.6.0
     ports:
       - "6379:6379"
     volumes: