build(deps): bump tonistiigi/xx from 1.5.0 to 1.6.0

Bumps tonistiigi/xx from 1.5.0 to 1.6.0.

---
updated-dependencies:
- dependency-name: tonistiigi/xx
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Dockerfile

@@ -50,7 +50,7 @@ ARG NYDUS_VERSION=v2.3.0
 ARG SOCI_SNAPSHOTTER_VERSION=0.8.0
 ARG KUBO_VERSION=v0.31.0
 
-FROM --platform=$BUILDPLATFORM tonistiigi/xx:1.5.0 AS xx
+FROM --platform=$BUILDPLATFORM tonistiigi/xx:1.6.0 AS xx
 
 
 FROM --platform=$BUILDPLATFORM golang:${GO_VERSION}-bookworm AS build-base-debian