chore(deps): update ghcr.io/atuinsh/atuin docker tag to v18.8.0 (#188)

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

Author: renovate[bot]

clusters/homelab/apps/atuin/atuin.yaml

@@ -44,7 +44,7 @@ spec:
               value: "true"
             - name: RUST_LOG
               value: info,atuin_server=debug
-          image: ghcr.io/atuinsh/atuin:v18.7.1
+          image: ghcr.io/atuinsh/atuin:v18.8.0
           name: atuin
           ports:
             - containerPort: 8888