chore(deps): update ghcr.io/open-feature/sync-testbed docker tag to v0.4.8 (#658)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -46,7 +46,7 @@ jobs:
           ports:
             - 8014:8013
         sync:
-          image: ghcr.io/open-feature/sync-testbed:v0.4.6
+          image: ghcr.io/open-feature/sync-testbed:v0.4.8
           ports:
             - 9090:9090
         sync-unstable: