chore(deps): update redis docker tag to v8

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| photoprism/photoprism | pinDigest |  → `5229f68` |
| redis | pinDigest |  → `46884be` |

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Reviewed-on: #3
Reviewed-by: t.behrendt <t.behrendt@noreply.localhost>
Co-authored-by: Renovate Bot <renovate@t00n.de>
Co-committed-by: Renovate Bot <renovate@t00n.de>

k8s/21_deployment_photoprism.yaml

@@ -18,7 +18,7 @@ spec:
         kubernetes.io/hostname: k3sh0
       containers:
         - name: photoprism
-          image: photoprism/photoprism:latest
+          image: photoprism/photoprism:latest@sha256:5229f68bce0293320547f35c733de584d7c2d5725a0efbddb68d7a118a8fc21c
           imagePullPolicy: Always
           resources:
             limits:
@@ -91,7 +91,7 @@ spec:
             - mountPath: /photoprism/storage
               name: storage
         - name: redis
-          image: redis:6-alpine
+          image: redis:8-alpine@sha256:81b6f81d6a6c5b9019231a2e8eb10085e3a139a34f833dcc965a8a959b040b72
           resources:
             limits:
               cpu: "500m"