chore(deps): update ghcr.io/buildkite/buildkite-mcp-server docker tag to v0.6.1

Author: renovate[bot]

registry/buildkite/spec.yaml

@@ -50,7 +50,7 @@ tags:
   - jobs
   - devops
   - testing
-image: ghcr.io/buildkite/buildkite-mcp-server:0.6.0
+image: ghcr.io/buildkite/buildkite-mcp-server:0.6.1
 permissions:
   network:
     outbound: