Update redis Docker tag to v8 (#18)

Co-authored-by: text-html-renovate[bot] <182508163+text-html-renovate[bot]@users.noreply.github.com>

Author: text-html-renovate[bot]

.github/workflows/test.yml

@@ -54,6 +54,6 @@ jobs:
 
     services:
       redis:
-        image: redis:7.4
+        image: redis:8.0
         ports:
           - 6379:6379