chore(deps): update grafana/k6 docker digest to 9481efe (#2068)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| grafana/k6 | digest | `82e44a4` → `9481efe` |

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examples/example-exemplars-tail-sampling/docker-compose.yaml

@@ -68,7 +68,7 @@ services:
       - ./config/grafana-dashboards.yaml:/etc/grafana/provisioning/dashboards/grafana-dashboards.yaml
       - ./config/grafana-example-dashboard.json:/etc/grafana/example-dashboard.json
   k6:
-    image: grafana/k6@sha256:82e44a45a38ed22bf5636fe50fe8a07967c3074f7aa66567c6a7501ab9bb3a9f
+    image: grafana/k6@sha256:9481efe0c1e12ede6af3caae289026001106dd6fcd462c61fa1c35ea565cb958
     network_mode: host
     volumes:
       - ./config/k6-script.js:/k6-script.js