chore(deps): move dawarich redis to v8 track

dawarich_redis was the last redis instance still on 7-alpine; the
closed PR #10 kept it as an "Ignored or Blocked" entry in the Renovate
Dependency Dashboard (issue #6). Bump to the already-running
redis:8.8.0-alpine digest and add apps/dawarich to the renovate redis
8.x allowedVersions pin. Data path /mnt/user/appdata/dawarich/redis
unchanged; redis 8 loads the existing RDB snapshots.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

renovate.json

@@ -95,7 +95,8 @@
       "matchFileNames": [
         "infra/redis/docker-compose.yml",
         "apps/nextcloud/docker-compose.yml",
-        "apps/immich/docker-compose.yml"
+        "apps/immich/docker-compose.yml",
+        "apps/dawarich/docker-compose.yml"
       ],
       "matchPackageNames": ["redis"],
       "allowedVersions": "/^8\\.\\d+\\.\\d+-alpine(?:\\d+\\.\\d+)?$/"