chore(deps): update tonistiigi/xx docker tag to v1.6.0 (#39)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [tonistiigi/xx](https://redirect.github.com/tonistiigi/xx) | stage |
minor | `1.5.0` -> `1.6.0` |

---

### Release Notes

<details>
<summary>tonistiigi/xx (tonistiigi/xx)</summary>

###
[`v1.6.0`](https://redirect.github.com/tonistiigi/xx/compare/v1.5.0...v1.6.0)

[Compare
Source](https://redirect.github.com/tonistiigi/xx/compare/v1.5.0...v1.6.0)

</details>

---

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Dockerfile

@@ -1,5 +1,5 @@
 # Easy crosscomple toolkit
-FROM --platform=$BUILDPLATFORM tonistiigi/xx:1.5.0 AS xx
+FROM --platform=$BUILDPLATFORM tonistiigi/xx:1.6.0 AS xx
 
 # Build the manager binary
 FROM --platform=$BUILDPLATFORM docker.io/library/golang:1.23 AS builder